[HN Gopher] Ultra compact GAN ATX power supply delivers up to 25...
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       Ultra compact GAN ATX power supply delivers up to 250 Watts
        
       Author : zdw
       Score  : 298 points
       Date   : 2022-05-27 02:31 UTC (20 hours ago)
        
 (HTM) web link (www.cnx-software.com)
 (TXT) w3m dump (www.cnx-software.com)
        
       | bradlys wrote:
       | Here's to hoping for titanium rated power supplies becoming the
       | norm like GaN chargers - and for a reasonable price!
        
       | Jaruzel wrote:
       | Looking at this, makes me wish (again!) that there was a globally
       | agreed colour scheme for Live/Neutral/Earth wiring....
        
         | deepsun wrote:
         | I always thought Neutral is White, Earth is Black, and Live is
         | everything else (like Red).
        
           | peoplefromibiza wrote:
           | Yellow & Green striped is the IEC standard for earth here in
           | Europe AFAIK
           | 
           | https://en.wikipedia.org/wiki/IEC_60446#Protective_earth_and.
           | ..
        
           | formerly_proven wrote:
           | As usual there's the American way and the International way.
        
             | deepsun wrote:
             | Stop dividing people! I'm International, by the way :)
        
           | Jaruzel wrote:
           | Here in the UK, Neutral is blue, Earth is Yellow & Green
           | striped, and Live is Brown.
           | 
           | Unless... the wiring is over ~30 years old, in which case
           | it's Black + Red for Neutral and Live.
        
           | jbotdev wrote:
           | In the US it's White for Neutral, Green for Ground, Black for
           | Hot, Red also Hot (usually for the other hot/phase on 240v or
           | three way lighting).
        
       | ParksNet wrote:
       | We need a new ATX standard with external power bricks and smaller
       | components. Giant ATX cases are unnecessarily huge, but laptops
       | are too small and noisy. There's not much of a middle ground.
        
         | toast0 wrote:
         | Like another poster said, Mini-ITX can be fairly small; I've
         | got some 3.3L cases (includes a 150W power supply). My case has
         | room for a 2.5" drive and a laptop optical drive (kind of,
         | there's a related model that has an opening for the optical
         | drive, mine just has the mounting place for it), you could get
         | a smidge smaller if you omit that. There are smaller cases
         | especially if you have and don't count an external power
         | supply. If you do MicroATX including a MicroATX case, that's
         | meaningfully smaller than ATX but there's no price premium. If
         | you want to get smaller, the CPU coolers are the tricky bit,
         | and I'm assuming you're ok with integrated graphics, GPUs and
         | their coolers are pretty immense as well.
        
         | Hamuko wrote:
         | Mini-ITX?
        
         | saxonww wrote:
         | There's plenty of middle ground. In terms of size, you have
         | Mini ITX as pointed out by another comment, and there's
         | MicroATX which is perhaps more common than regular ATX. And of
         | course there are several mini systems like the Mac Mini, Intel
         | NUC series, and derivatives/copies of the NUC.
         | 
         | There are a lot of case options for small Mini ITX systems, I'm
         | using an NCase M1 which is a 12-13L by volume case. There are
         | smaller cases, but the smaller the case, the less flexible it
         | is with configurations, which is one reason they large ATX
         | cases are still popular; it seems like a lot of enthusiasts
         | like clear side panels and rgb light shows and so forth, and a
         | tiny case isn't as exciting.
         | 
         | There are also multiple PSU size options. The NCase M1 I
         | mentioned can use a regular ATX PS, but an SFX power supply
         | fits better; SFX seems like maybe half the volume of a regular
         | ATX PS. There is also SFX-L, which is a bit bigger so it can
         | house a larger fan. These smaller PS standards are typically
         | lower power, although you can get 650W+ SFX supplies now I
         | think. Silverstone and Corsair were regarded as having the best
         | SFX supplies last time I was looking.
         | 
         | Finally, there are a couple of options for external power
         | bricks like you suggest. As mentioned elsewhere there is a
         | PicoPSU which is a DC/DC converter the size of a 24 pin ATX
         | socket. It just plugs into the ATX socket on any regular ATX-
         | compatible motherboard and has some cables attached to the
         | sides for peripherals. There's also the 'Thin Mini-ITX'
         | standard, which is I think intended for digital signage and
         | industrial stuff, but if your requirements are modest you can
         | use these for a desktop also. They integrate a DC/DC converter
         | and use a 19V laptop ac adapter. The ones I've seen are best
         | suited to on-chip graphics and m.2/msata drives, though.
        
           | pornel wrote:
           | There are plenty of products, but they're all underwhelming.
           | Form factor and position of all the key components is so
           | unfortunately mismatched, that no matter how you arrange
           | them, there has to be a ton of wasted space.
           | 
           | It doesn't help much that you can have a small motherboard.
           | You will need a CPU cooler stick out the middle of it, which
           | already takes most of the space you have above MB's
           | footprint. If you insert a GPU without a riser cable, you'll
           | have to move the PSU to the side of the MB, and that's
           | already almost as chonky as a regular ATX. So you're forced
           | to deal with airflow-choked GPU, low-profile coolers, and no
           | room for a powerful PSU.
           | 
           | If you instead opt for an easy-to-cool CPU and no discrete
           | GPU to save space, it's still a massive box for a computing
           | power of a tablet.
        
             | saxonww wrote:
             | Maybe you're interested in a NUC, then.
             | 
             | I remembered earlier there is an alternative GPU form
             | factor for laptops called MXM. You can get desktop boards
             | that accept these, I think they are called Micro-STX or
             | Mini-STX. They are small, and the GPU is a flat module that
             | plugs in more like a daughterboard than a PCI card. You're
             | still looking at low-power CPU though.
             | 
             | I'm not sure what your vision looks like, to be honest. I
             | think you want a laptop without the integrated screen and
             | keyboard. That's a NUC, IMO; if an integrated or laptop-
             | grade GPU isn't good enough, you'd want to do eGPU over
             | thunderbolt I guess.
        
         | vladvasiliu wrote:
         | Maybe there could be some use if the external brick could be
         | standard, so you'd only have to carry the actual computer.
         | 
         | But I personally would much prefer having to lug around a
         | marginally bigger box instead of two smaller ones. Fewer cables
         | to trip over, etc.
         | 
         | Also, if the case is a bit bigger, it will probably be able to
         | house a bigger cooler, so it should be quieter, if I'm looking
         | for a powerful computer.
         | 
         | If I'm OK with a regular middle of the road setup, there
         | already are plenty of options from OEMs. I'm thinking HP
         | Desktop Minis. Dell, Lenovo and Fujitsu also have similar
         | offerings, though I'm not familiar with them. They can be a bit
         | noisy under load, though.
        
       | Nursie wrote:
       | So about quarter the size of a standard SFX PSU, which is pretty
       | cool. But also about a quarter the power the 'biggest' ones can
       | provide.
       | 
       | I can see this being really good for (for instance) boxes like my
       | fileserver which has a 65W TDP i3 in it and a bunch of SSDs, or
       | compact media boxes that just have a processor and iGPU.
       | 
       | Unfortunately the way things are going in the world of PCs, you
       | aren't going to power much of a modern dGPU from that.
        
         | Gigachad wrote:
         | The example showing two linked together for 500w was
         | interesting. This would allow more compact or oddly shaped
         | desktops.
        
       | divbzero wrote:
       | s/GAN/GaN/
       | 
       | GAN [1] happens to be a machine learning construct. 250 W of
       | electrical output would be rather surprising.
       | 
       | [1]: https://en.wikipedia.org/wiki/Generative_adversarial_network
        
         | mauvehaus wrote:
         | Capitalization is the difference between "I helped my Uncle
         | Jack off a horse" and ...
        
         | oriolid wrote:
         | I was totally expecting hardware designed by GAN :) Using
         | genetic algorithms for hardware design is already old trick.
        
         | paulmd wrote:
         | scoff all you want, this was the plot of The Matrix!
         | 
         | (the original script was written with the sensible "using
         | humans as a biological computer" angle but they worried
         | audiences wouldn't get that newfangled computer thing in the
         | basically prehistoric year of 1999, so they changed it to be
         | humans generating power which... isn't how thermodynamics
         | works!)
        
           | prutschman wrote:
           | "But that's crazy, Morpheus. Thermodynamics says.."
           | 
           | "And where did you learn about physics, Neo?"
           | 
           | "..... In the Matrix...."
        
           | [deleted]
        
           | bombcar wrote:
           | You could have combined it with Idiocracy - all the people in
           | the Matrix act slow and dumb because most of their brainpower
           | is being used to run weather simulations or whatever you'd do
           | with a world-wide supercomputer.
        
           | strbean wrote:
           | Damn, that would have been much cooler!
        
       | javajosh wrote:
       | The cables are bigger than the PSU. Has anyone ever experimented
       | with putting edge connectors on a motherboard PCB for power? And
       | edge connector for PCI and memory and m.2? In this way you could
       | build out a very flat PC with commodity parts, since all the
       | components would be parallel to each other and the motherboard.
        
         | kraftman wrote:
         | You can get 90 degree adapters for the motherboard power
         | connector and PCI, and low profile ram. the issue then is
         | getting a low profile heatsink for the CPU. There are
         | waterblocks but not many with edge ports.
         | 
         | There are also boards like this that have the RAM mounted flat,
         | a lower profile set of ports on the back, and take in 19v DC:
         | https://www.asrockind.com/en-gb/IMB-193
        
           | javajosh wrote:
           | _> the issue then is getting a low profile heatsink for the
           | CPU_
           | 
           | You'd have to make something custom, but I think it would be
           | much simpler than typical heat sinks. With air cooling, the
           | vertical placement would be ideal, since convection will tend
           | to suck cool air from the bottom and release it on the top.
           | (I think the iMac does/did this). Even for water cooling, it
           | would be simpler with far fewer turns in the pipe. Plus, I
           | just like the idea of laying everything out flat instead of
           | the weird 3-D origami that is modern PC design.
        
         | kayson wrote:
         | Dell PowerEdge Servers do this. And they have 1.1kW PSUs!!
        
           | mrb wrote:
           | Indeed. Edge connectors are common on servers with hot-
           | swappable PSUs.
        
           | unwind wrote:
           | Wow, didn't know they thought it was important enough of a
           | feature to put it in the name of the product. :)
        
         | c_o_n_v_e_x wrote:
         | You should look at CRPS form factor power supplies, they have
         | the edge connector you are referring to. ATX12VO also addresses
         | the large legacy ATX connector.
        
         | jonah-archive wrote:
         | The SGI O2 was built like this (power & all bus connections
         | were off an edge connector), some good pics of the mobo at:
         | https://bukosek.si/hardware/collection/sgi-o2.html#pics
        
         | jabl wrote:
         | Wasn't there some upcoming PSU spec that dropped the 5 and 3.3V
         | rails leaving only 12V? What happened to that?
         | 
         | Edit: Yes, the "ATX12VO" spec.
        
           | rocqua wrote:
           | Yes, but it seems unlikely to hit consumer markets soon. It
           | is mostly interesting for OEMs apparently. I hope I am wrong
           | though.
        
             | vladvasiliu wrote:
             | Aren't OEMs already able to do pretty much what they want?
             | 
             | I have a desktop HP that has a standard-sized PSU but has a
             | weird connector that only plugs into the motherboard. The
             | drives are powered from a separate connector that also
             | plugs into the motherboard. And the PSU - MB connector is
             | much smaller than standard ATX.
        
               | rocqua wrote:
               | HP can control the full stack. MB and PSU at the same
               | time. But smaller OEMs might want to not have to
               | manufacture their own totally custom components. So it
               | makes sense for them to standardize. If not for
               | interchangeablity then to ensure you can sell your custom
               | parts to other OEMs.
        
           | bombcar wrote:
           | I know we don't need 5v for spinning drives anymore, but what
           | voltage does the CPU want to see? If it's not 12V aren't we
           | just moving the voltage drop equipment onto the motherboard?
        
             | coder543 wrote:
             | The VRMs for the CPU have already been on the motherboard
             | for a very long time, maybe always? CPUs operate at very
             | low voltages with very high amps. For a lot of reasons, it
             | makes sense to keep that as close to the processor as
             | possible.
        
             | heretogetout wrote:
             | Consumer CPUs these days are at around 1.4 to 1.5 volts.
             | Not sure about server, but it's probably close.
        
             | hnuser123456 wrote:
             | CPUs are around 1-1.2v. However, they can occasionally pull
             | 100-200+W. Moving 200W at 1V means 200A. Resistive losses
             | scale proportional to amperage at constant voltage, and
             | inversely proportional to voltage at constant power. 200A
             | needs a LOT of copper to not get blistering hot, the amount
             | you would find in all the traces connecting a CPU to the
             | VRMs on the motherboard, probably around 4 ounces just to
             | carry the power a few inches. 200W at 12V is 16.7A, which
             | can be shuttled much longer distances with less material at
             | the same efficiency, in the ~foot long cable between the
             | PSU and motherboard. Additionally, pluggable connectors are
             | high resistance spots in the circuit unless they make very
             | good contact, and susceptible to overheat and melt when
             | carrying too much current.
        
       | zasdffaa wrote:
       | Could an EE comment on the safety of this.
        
         | solarkraft wrote:
         | Not an EE, but it's a consumer product sold through non-shady
         | channels, so it's presumably very safe.
        
       | aix1 wrote:
       | Could someone ELI5 what makes GaN PSUs/chargers more efficient
       | than earlier technologies?
        
         | pjc50 wrote:
         | The scientific answer appears to be "high Johnson's figure of
         | Merit", for which the primary source is a 1965 journal:
         | https://worldradiohistory.com/hd2/IDX-Site-Technical/Company...
         | (you can go forwards by editing the URL)
         | 
         | There are two factors:
         | 
         | - you need a high breakdown voltage, so that for a given
         | voltage you want to switch you can make the transistor channel
         | as short as possible; shorten the physical distance that charge
         | carriers have to flow in the semiconductor.
         | 
         | - you need a high maximum drift velocity, which governs the
         | rate at which charge carriers can flow through the
         | semiconductor
         | 
         | Those contribute to reducing the on-resistance of the
         | transistor, thereby decreasing its heat output for a given
         | size.
        
         | diffeomorphism wrote:
         | It is not so much about efficency but about size.
         | Galliumnitride generates less heat than silicon, so you can
         | make much smaller power supplies.
        
           | Doxin wrote:
           | If I recall correctly GaN transistors also just generally are
           | better in a lot of metrics. Faster switch times, Lower
           | resistance, Higher permissible voltages, etc. It really does
           | look like a miracle technology.
        
             | rowanG077 wrote:
             | Are they good for logic (CPUs, GPUs etc) as well or just
             | for power applications?
        
               | namibj wrote:
               | In theory, but they are hard to miniaturize for logic
               | ICs.
        
               | kf7njh wrote:
               | I would argue probably not. GaN has a higher bandgap
               | voltage (3eV iirc... 1eV for Silicon), which means a CPU
               | would need to be run at a higher voltage.
               | 
               | As a quick rule of thumb for huge transistor count ICs:
               | Power (heat) = freq*Voltage^2
               | 
               | I won't go into detail, but you can see how for a CPU
               | designer decreasing voltage is critical to increasing
               | speed. Remember a decade ago when CPUs were like 1.2V and
               | we hit this ~3GHz "wall"? But now due to breakthroughs in
               | process nodes, CPUs are running I think ~0.8V but
               | boosting up to 5GHz.
               | 
               | If we make the same CPU on a GaN process, the transistors
               | would probably need ~3V to switch, and thus need to be
               | run about 9x slower to meet the same package power (or I
               | guess you could run it at the same speed but then try and
               | figure out how to cool a 9x higher TDP CPU).
               | 
               | Furthermore, GaN is difficult to manufacture into a
               | monocrystaline perfect lattice compared to Silicon. You
               | can image that for modern 7nm/5nm nodes, where there are
               | sometimes angstroms of distance in a transistor, having a
               | foundation full of defects can be devastating to the
               | yield.
               | 
               | Power electronics is a totally different domain with
               | different challenges. In this area GaN excels, but for
               | ICs I don't think it makes sense. Let's see in 20 years
               | though. GaN is relatively new compared to Silicon and
               | might just need some further refinement.
               | 
               | Just my 2c though. Someone correct me if I'm wrong.
        
           | yetanotherloser wrote:
           | Converting less of the switched energy to heat IS efficiency;
           | there's no difference.
        
       | londons_explore wrote:
       | The littlebox challenge back in 2014 required 3 watts/cm^3 to
       | compete...
       | 
       | This 'ultra compqct' only offers 1.18 watts/cm^3 in 2022.
       | 
       | While this might be the best on the market, it is far from what
       | is technically possible.
        
         | tecleandor wrote:
         | But that was an inverter, so DC --> AC. But also, I don't know
         | if that really makes a difference :P
        
       | causality0 wrote:
       | Is it just me or are the size benefits of GaN power supplies
       | overblown? The 100w GaN type-c charger for my new laptop is less
       | than ten percent lighter than the 100w charger for my decade-old
       | Dell, while being six times more expensive to replace.
        
         | ed25519FUUU wrote:
         | Isn't it a lot _smaller_ (not lighter) though? I think the main
         | benefits are size and efficiency, not weight.
        
           | causality0 wrote:
           | It might be about thirty percent smaller by volume. It's not
           | any more convenient to carry around because instead of being
           | a candy bar shape it's perfectly square and actually wider
           | than the old one. While not related to it being a GaN
           | charger, it being a permanently attached type-c connector is
           | a recipe for disaster considering how much more delicate it
           | is than a traditional laptop charger. I'm probably going back
           | to a ThinkPad for my next laptop and the charger connector is
           | not an insignificant reason why.
        
       | noobermin wrote:
       | I hate to be the one but a) this means fixing these psu's are
       | going to be even harder now and b) at some point people are going
       | to have to worry about _energy intensity_ (W /m^2) exceeding
       | values where the devices themselves will melt. That said,
       | interesting tech. It feels like a lot of new tech news these days
       | is just furthering gimmicks (adding "blockchain" to this or ML
       | applied to something that didn't need it) but this is actually
       | cool and could open a host of new applications.
        
         | csours wrote:
         | Do people fix PSUs?
        
           | tinco wrote:
           | I fixed mine once. I lived in a university town, which caused
           | the small unusual circumstance that no local store had a 700W
           | power supply in stock, but there was a electronic parts store
           | that had the capacitor I needed to replace.
           | 
           | Besides the capacitor only costing 10 cents and a new one
           | around a hundred bucks the advantage for me was that I had
           | fixed the whole thing within na hour or two including
           | diagnosing the issue and the bike ride to the shop.
           | 
           | I was back on my PC that same night, and 5 years later that
           | same PSU now well over ten years old is still going strong.
        
           | noobermin wrote:
           | Yes?????????
        
             | nwiswell wrote:
             | Awesome! I've got about a hundred server power supplies
             | that need fixing, what do you charge?
        
               | londons_explore wrote:
               | If you have a hundred identical power supplies that need
               | fixing, they probably all have the same fault, and the
               | fix will probably be 3 minutes labour + 20 cents in parts
               | after the first one. That's totally worth doing.
        
               | justahuman74 wrote:
               | Too much.
               | 
               | You fix a PSU cause you know what you're doing and have
               | the time, not because it's economical to do for someone
               | else
        
               | nwiswell wrote:
               | Hmm! It certainly seems like if it's worthwhile for
               | anyone to do with unspecialized labor, then it would
               | certainly be worth doing for a specialist.
               | 
               | Why is it that I've never heard of a power supply repair
               | technician in a data center?
        
               | tinco wrote:
               | Because data centers don't care about ewaste. It is
               | cheaper to have power supplies redundant and in stock
               | than it is to have a technician on retainer.
        
               | nwiswell wrote:
               | Server power supplies are expensive, and data centers
               | sure do care about the bottom line.
               | 
               | If it costs $20 to fix a $100 power supply, why would you
               | replace it?
        
               | c_o_n_v_e_x wrote:
               | Actually I did a study on this (I'm a PM for a small
               | server company) about a year ago with data scraped from a
               | popular US based online vendor.
               | 
               | For PSUs >1000 watts, I found that server supplies are
               | cheaper both on a relative (more watts / dollar) and
               | absolute cost basis than ATX form factor supplies.
        
               | jandrese wrote:
               | Aren't the >1k watt ATX power supplies usually the "gamer
               | edition" ones with huge markups? They cost a lot because
               | they are a small niche--very few PCs need power supplies
               | that big, and the ones that do are running multiple
               | wildly expensive GPUs so budget is clearly not a concern.
               | 
               | There's probably more legitimate demand on the commercial
               | side for >1kw PSUs so they can enjoy larger economies of
               | scale.
        
               | tinco wrote:
               | How frequent are the failures? It costs a lot less than
               | $20 to repair a broken power supply, but if you break
               | less than $5000 worth of power supplies per month you're
               | not breaking even on the technician not even counting the
               | management overhead.
               | 
               | I don't think small cost savings like that are going to
               | be implemented simply because it makes the operation more
               | complex without landing any manager a big fat bonus.
               | 
               | Unless I'm grossly underestimating the failure rate of
               | those supplies?
        
               | ClumsyPilot wrote:
               | > It certainly seems like if it's worthwhile for anyone
               | to do with unspecialized labor, then it would certainly
               | be worth doing for a specialist
               | 
               | 'Anyone' could be a penniless student and his time costs
               | little, specialist may charge $40 per hour.
               | 
               | Also even ideal free market has cost of transaction,
               | discoveravility, etc.
               | 
               | Hospitals have repair technicians, but why would you need
               | one spesifically focusing on power supplies - he does not
               | need different training or equipment
        
               | tecleandor wrote:
               | I don't know if you're trolling but, probably it's all
               | about support contracts and liability.
               | 
               | - If your hardware hasn't reached EOL, it's probably
               | under a warranty or support contract. So you just let
               | your provider swap/fix it.
               | 
               | - If you tinker with anything and there's a problem with
               | the rest of the hardware, they'll probably won't honor
               | the warranty or support contract, or you could have
               | problems with your insurance.
               | 
               | If it were a home user fixing a PSU... that's a different
               | thing.
        
           | bradlys wrote:
           | Clearly the 0.01% of people who have even _opened_ a PSU are
           | going to chime in and say it's necessary.
           | 
           | I've torn mine apart and replaced fans in them and such but
           | I've never had to resolder any parts onto them. If a PSU dies
           | - it tended to do it violently and was so cheap that it
           | wasn't worth doing it. All the name brand ones I've had never
           | had any issues and same for the dozens of other people I
           | knew. (Or computers I worked on or built or sold to others...
           | or when I did IT and saw literally thousands of computers...)
        
         | Gigachad wrote:
         | I wouldn't even consider fixing a psu. It's dangerous high
         | voltage electronics so messing it up could result in a fire or
         | personal harm.
         | 
         | And they are standardised. Makes more sense to just replace
         | them.
        
           | kadoban wrote:
           | I've been told they have big scary capacitors in them as
           | well. Never fun trying to fix something where unplugging it
           | isn't even enough to be safe.
        
             | ClumsyPilot wrote:
             | Wait for a few minutes before opening it up, check with a
             | multimeter, etc. Mains voltage isn't that scary if you
             | follow basic precautions
        
               | kadoban wrote:
               | Is a few minutes enough? My impression was they could
               | remain charged for long periods.
        
         | toast0 wrote:
         | How many people fix their psu vs eWaste when they stop working,
         | which is usually 5+ years after they were made, unless they
         | were made with unusually poor components or design?
         | 
         | I don't necessarily need a smaller power supply, but options
         | are nice.
        
           | zepolen wrote:
           | Most boards have a couple components that are on the weak
           | side and fail, usually a capacitor. Any electronics shop can
           | fix it for at most $20, or you can do it yourself for the
           | cost of a 20 cent component though usually not worth the
           | time. Beats paying $100 for a new PSU.
        
         | tinco wrote:
         | Fixing PSU's has never been hard. And actually looking at the
         | board it looks like this is even easier to take a part and work
         | on than the PSU I have repaired.
        
       | torginus wrote:
       | I think the chief limitation here is the ATX standard itself.
       | Modern devices could make do with a single 12V rail (especially
       | at this wattage), that would reduce the cabling and simplify the
       | PSU circuitry as well.
       | 
       | A lot of prebuilt OEMs and consoles and not to mention laptops
       | already use this approach.
        
         | PossiblyKyle wrote:
         | On one hand, I definitely agree.
         | 
         | On the other, my issue is that motherboards are already one of
         | the least reliable components in your PC, and introducing even
         | more complications to them just makes the situation (and the
         | cost of replacement) worse
        
           | bradfa wrote:
           | Going to only 12V power to the motherboard doesn't actually
           | make them much more complicated, or any more complicated
           | really. Like half of a modern motherboard design today is
           | just power supplies anyways, as all CPUs will do voltage
           | scaling to save power. It's not like your CPU takes 3.3V
           | input directly, most are running in the 0.8-1.5V range, even
           | DDR4 is 1.2V, and the CPU is the majority of the consumption
           | on the actual motherboard (high power graphics cards usually
           | have their own 12V input connector, the PCIe edge cannot
           | transfer enough).
        
             | dicknuckle wrote:
             | I expect motherboards could be more reliable if there was a
             | standard 12v to 5v, 3.3v, 1.5v etc pluggable converter that
             | they all used. It could cut down on E waste. Instead of
             | having to discard an entire motherboard, the low voltage
             | converter board could be swapped out and
             | repaired/discarded. The same companies that make ATX power
             | supplies could also make the discreet low voltage
             | converters. ATX innards could be smaller, less wiring
             | between components.
             | 
             | No that's silly, we should continue to use a design from
             | 1995, itself replacing a design from 1981.
        
               | bradfa wrote:
               | Well, sure that'd be nice, but it would add quite a lot
               | of cost. High current carrying connectors are not free.
               | 
               | You can buy a nice AMD Ryzen motherboard for like $80
               | retail (Newegg shows $59 is where new unopened ones
               | start). Normal electronics supply chain and shipping
               | margins means it cost roughly half that to manufacture
               | it. So on a $40 bill of materials and labor cost if you
               | add even just $1 to make something
               | better/modular/whatever then you're adding a significant
               | amount in terms of percentage cost increase.
               | 
               | As much as reducing electronics waste is a worthy goal,
               | the economics of it aren't aligned quite yet in today's
               | world.
        
       | Ayesh wrote:
       | I have a laptop that draws 240W over a square slim tip, and
       | recently saw a 240W GaN power brick. Like the photo in the
       | article, it's comparable to an iPhone in size, but what prevented
       | me from buying it was the weight (400g) and the price ($155
       | IIRC).
       | 
       | I think the sweet spot of GaN is in wall adapters that deliver
       | 18-45W over USB-A/C for mobile devices rather than PSUs where the
       | size/weight doesn't matter as much.
        
         | TruthWillHurt wrote:
         | I actually have a 100W GaN charger for my 100W Razer Stealth
         | 13''. Super compact and great for travel. The new Razer models
         | actually come with the GaN charger included!
        
       | genewitch wrote:
       | $145 is pretty steep, and I'd like to see the Vpp (also called
       | ripple) before considering this. I currently use picoPSU (ASIN
       | B005TWE5E6), 50W and 80W versions to power 7th and 8th gen atoms
       | and celerons. I use a "UPS" style 12VDC PSU connected to a fairly
       | large sealed lead acid battery - about 4x the volume of a
       | standard UPS battery. As far as my measurements go with the
       | induced noise from the PSU for radio reception work, it seems to
       | work pretty good. I've looked at using SBCs instead, but you're
       | never really going to get away from buck/boost on boards, since
       | some things need 3.3 or less volts (memory, etc). The picoPSU
       | also have survived for years up in elevator attics with all of
       | the machinery and dust. never had an outage caused by the picoPSU
       | or the attached 12V UPS stuff.
       | 
       | I wonder if it is possible to run more than one board off the
       | same PSU. I know you can run a board off multiple PSUs, but is
       | the inverse true? If i ever get a new batch of these 25W TDP
       | computers racked, having 2 of these connected to two UPS and 6
       | computers might be cool. It's just the ATX connector that needs
       | population, i use NVME whenever possible, no GPU, no cards, just
       | USB and ethernet onboard.
        
         | rektide wrote:
         | > _I wonder if it is possible to run more than one board off
         | the same PSU._
         | 
         | Absolutely. There's something I can't remember about signal
         | lines that need to be set up, but yet, people have been running
         | multiple computers off as single supply for a long long long
         | time now.
         | 
         | Also worth warning people ahead of time, it's hard to predict
         | what kind of specific power consumption a motherboard will
         | have. There's so many power rails going in. 3.3V, 5V, 12V,
         | -3.3V... Making sure that _each_ rail is adequately rated for
         | additional motherboards can be a challenge. Ideally one would
         | test each supply line, one by one, to try  & figure things out,
         | & compare against rated specs of the power supply.
         | 
         | Intel's been pushing a new spec called ATX12VO, short for
         | 12-volts-only, which does away with all the other rails & has
         | the motherboard expect 12v. This would make it much easier to
         | understand what power consumption is. I do seem to recall some
         | of the new ATX specs (3.0?) also kind of expect power-consumers
         | to declare how much power they expect to use, as a
         | safety/planning feature, which could complicate this one easy-
         | to-do hack (unless there's some way for the additional
         | motherboard/motherboards to also declare their power draw).
         | This might only be ATX3.0's new 12VHPWR connector, which works
         | alongside PCIe 5.0-- not sure if it also impacts motherboards
         | or not.
        
           | robocat wrote:
           | > Making sure that each rail is adequately rated for
           | additional motherboards can be a challenge
           | 
           | Buy a cheap inline tester and leave it always in? Something
           | like: https://www.google.co.nz/search?q=Power+Supply+Tester+D
           | igita...
        
           | paulmd wrote:
           | These days the 3.3v rail and -3.3v rail are practically
           | vestigial (iirc the major consumer on those rails was floppy
           | disk drives...) and 5V is mostly used to drive SSDs and USB
           | devices. Almost everything runs off 12V these days - which is
           | the whole point behind the 12VO standard, just make
           | everything use 12V and step it down at the point-of-
           | consumption for the handful of things that still need
           | something else.
           | 
           | So basically I wouldn't worry about motherboard compatibility
           | due to 5v, 3.3v, and -3.3v rails - there just isn't much of
           | anything still being done on those rails, and the things that
           | do use it pretty much are the same across motherboards
           | (because they're things that are _plugged into_ the
           | motherboard, not the motherboard itself).
        
             | mschuster91 wrote:
             | > and 5V is mostly used to drive SSDs and USB devices.
             | 
             | The most important 5V rail is 5VSB - it powers wake-on-LAN
             | and on some systems wake-via-bluetooth. The interesting
             | question is, is it more efficient to _always_ let 12V- >5V
             | regulators run for 5VSB or to use an extremely small
             | separate regulator?
        
               | paulmd wrote:
               | > The interesting question is, is it more efficient to
               | always let 12V->5V regulators run for 5VSB or to use an
               | extremely small separate regulator?
               | 
               | To complicate this further, full system power-off is not
               | the only time you want to do wake-on-lan... if you want
               | to wake from _system sleep_ then you have to be running
               | the 12V rail anyway, because that 12V rail drives the
               | VRMs which drive Vcore and Vmem. No 12V rail means you
               | lose your memory and CPU state...
               | 
               | As such I don't think you can really frame this as
               | "having a separate 5V regulator with the 12v rail turned
               | off", or at least that use-case must exist _in addition_
               | to the deep-sleep use-case, it cannot supplant it
               | entirely.
               | 
               | Anyway though, power-supply 5V rails are usually much
               | much larger than they need to be, and that has higher
               | loss inside a transformer. Even if you make that a solid-
               | state thing inside the transformer, moving power at 5V is
               | less efficient than moving it at 12V and stepping it down
               | at the point-of-consumption. So actually the answer is
               | probably that it's more efficient to always run a step-
               | down regulator.
        
               | glowingly wrote:
               | To be fair, something is stepping it down from AC, and
               | many modern PSUs step everything down from a common DC
               | rail using DC-DC conversion (i.e, 12V, 5V, 3.3V, etc are
               | all generated from a source DC voltage). Then things like
               | the CPU and GPU have long moved off of the 3.3V rails to
               | harness the 12V rail for DC-DC conversion in various VRM
               | stages, down to <<2V.
               | 
               | My main appreciation for ATX12VO (12 volts only) is the
               | MB can choose to right size the 5V and 3.3V rails
               | appropriately. M.2 slots are driven from 3.3V only (even
               | if M.2 devices step it up or down for their specific
               | uses). A board with 4 M.2 slots will have a different
               | potential 3.3V power demand than a board with only 2
               | slots. Typically, a decent board will have 1 M.2 2230 A
               | or E slot for WiFi, and 1-2 M.2 2280/22110 M (and rarely
               | B) slots for M.2 storage. PCIe x16 lanes will have 9W of
               | 3.3V, as part of their 75W total power (the remaining 66W
               | is 12V).
               | 
               | As noted earlier, 5V is heavily I/O driven. A board with
               | 15 USB ports can expect to need more 5V than a stingy
               | board with only 8 (both are accounting for front I/O
               | headers).
               | 
               | I'd rather the MB have to right-size the 3.3V and 5V
               | rails, than forcing every PSU to include copious amounts
               | of 3.3 and 5 just to cover every edge case.
               | 
               | Sure, it's a tiny bit of potential efficiency. It's also
               | passing a bit of cost from the PSU to the board itself.
               | Sadly, it does seem ATX12VO's main impact will be lost.
               | OEMs are going to continue with their custom PSUs with
               | unique connectors and the DIY vendor + consumer market
               | has largely turned their backs to this.
        
         | aidenn0 wrote:
         | Can you show me what you mean by the UPS style PSU? That setup
         | sounds like it would be great for keeping my mini server up
         | during power outages (Xeon-D also running off of a picoPSU).
        
           | genewitch wrote:
           | sure, ASIN B00EAIG17E "DROK 110V 220V UPS Battery Backup
           | Uninterruptible Switching Power Supply 12V 120W 110V-240V to
           | 13.5V DC 50/60Hz with Battery Interface for Charging"
           | 
           | When you remove mains power it switches over instantly enough
           | that the computer doesn't notice. There's no serial port on
           | it so the computer has no way of knowing that it's on battery
           | - but it was also only $26 shipped. No wires or battery or
           | anything. I happen to have a few of the trimpot breakouts
           | specifically for setting voltages, so i just made sure that
           | when the PC was powered it was getting the correct voltage
           | without sagging below 12.2ish under load _at the output
           | terminal of the PSU_. It also has a little trimpot on the
           | board for adjusting the voltage.
           | 
           | P.S. I'm not sure if Drok has a lot of knockoffs or not, i do
           | know that i like that brand well enough, never had anything
           | bought from them break in a weird way. I have slagged a few
           | of their "waterproof" 24VDC boost converters, though!
        
         | MezzoDelCammin wrote:
         | it's not "that" steep once You consider the form factor and the
         | technology used.
         | 
         | Generally the most You can get from a PSU this size would be
         | those forementioned USB-C PD bricks. Those would these days get
         | You at max about 100W for probably not less than 50-60USD
         | (cheap Chinese models, more if branded).
         | 
         | Multiply that 2.5x (250W instead of 100W) and suddenly You're
         | pretty close to the price.
        
       | walrus01 wrote:
       | GaN stuff is also used in the smallest and highest power compact
       | tx power amplifiers in the rf chain for the buc/sspa on two way
       | geostationary satellite terminals now. Some of the BUCs now are
       | 1/3 the size of 12 years ago.
       | 
       | Other small and dense terrestrial microwave and millimeter wave
       | things use gan power amps too.
        
       | rektide wrote:
       | I was going to criticize & point out how usb-c chargers at and
       | over 100W are just so small, but there's a photo comparing it to
       | an iphone & ok, it looks adequately impressively dense! (I have a
       | >2 year old 100W charger that is 66x64x30mm, this 250W unit is
       | 170x50x25)
       | 
       | It's been such a great synergy. Energy efficiency has been a
       | concern already yes, but I really view usb-c chargers as pushing
       | the consumerization & massification & development of this
       | technology to the superb, common, un-exotic levels it's come down
       | to. We just got tired of doing less good, actively explored
       | trying to use a somewhat harder to drive switching semiconductor,
       | & have reaped great rewards. Miniaturization mandated
       | optimization & we all win. I really think the interchangable-
       | parts/modularity & resulting competition that usb-c begot started
       | this ball rolling.
       | 
       | (Hoping USB-PD, with it's bump from 20 up to 48V, once again
       | proves another huge win!)
        
         | hangonhn wrote:
         | > (Hoping USB-PD, with it's bump from 20 up to 48V, once again
         | proves another huge win!)
         | 
         | Can someone explain to me why 48V? Is there something special
         | with 48V or beyond? The reason I ask is because some cars now
         | have electric turbos and the manufacturer had to switch to a
         | 48V system. Just curious what the benefits of higher voltage is
         | and if 48 is somehow special.
         | 
         | Thanks in advance.
        
           | spookthesunset wrote:
           | At 48v you can use much smaller gauge wire than at 12v. Which
           | means lower cost, less weight and a smaller footprint for
           | your wire harnesses.
           | 
           | One of the things that can "get you" with these higher
           | voltage systems is you can't use them to jumpstart the
           | present majority of cars. While I've yet to actually see a
           | higher voltage car, I would hope they'd put warnings by the
           | battery to remind the user that "hey, don't try to jumpstart
           | your friends car with this battery!"
        
           | aparks517 wrote:
           | Power is the product of current and voltage. To transfer much
           | power at a low voltage requires a large current. Supporting a
           | large current without getting hot and melting requires large-
           | diameter wire. Other components may also be bulky or
           | expensive if they have high current-handling requirements.
           | 
           | I seem to recall that somewhere around 50 volts is a magic
           | number from a safety/regulatory perspective. It might also
           | have something to do with semiconductor breakdown voltage,
           | but maybe I'm out of date on that.
        
           | Dave_Rosenthal wrote:
           | My understanding is that 50V is the established threshold
           | above which safety to humans starts to be a factor. So,
           | applications that want high powers, without the penalty of
           | large wires nor the penalty of the safety requirements of an
           | HV system, converge to 48.
        
             | avhon1 wrote:
             | > the established threshold above which safety to humans
             | starts to be a factor
             | 
             | Specifically, 50 volts is approximately the threshold above
             | which electricity can pass through the skin and shock you.
             | Lower voltages will only shock humans if they have a way to
             | bypass some of the skin, like wounds or tight-fitting metal
             | jewelry. Otherwise, the resistance of skin is high enough
             | to prevent the flow of electricity. That's why you can
             | touch both terminals of a 12V car battery at the same time
             | and almost certainly not be shocked.
        
         | jsmith45 wrote:
         | I my complaint that they are calling this atx, when the only
         | thing remotely ATX about it is being designed to work with the
         | atx motherboard power connector.
         | 
         | This in no way meets the atx form factor for power supplies,
         | neither the original, nor the 12V version. Like I could forgive
         | it if it failed to be a rectangular prism in favor of having
         | more open space, as long as it had a frame with proper mounting
         | points.
         | 
         | And I could also forgive it if they went with the rectangle,
         | but far shorter than the official 140mm depth (that has always
         | been mandatory per intel specs), given that the market already
         | accommodates non-conforming lengths, and this could be made to
         | not require the bottom of case mounting holes, allowing for
         | absurdly short lengths.
         | 
         | But the photos show none of that, and just a fully custom form
         | factor, without any apparent mounting mechanism.
        
           | tomtheelder wrote:
           | The form factor and mounting design of the power supply are
           | not parts of the ATX spec. The pin layout & shape, voltages,
           | signaling, etc are what are specified.
           | 
           | This is an ATX power supply. It is just designed for very
           | small cases that would never be able to accommodate the
           | existing standard configurations.
        
             | D13Fd wrote:
             | >The form factor and mounting design of the power supply
             | are not parts of the ATX spec. The pin layout & shape,
             | voltages, signaling, etc are what are specified.
             | 
             | Did you just pull this out of nowhere?
             | 
             | Look at ATX Specification v. 2.01 section 4.1, page 18-20.
             | It specifies the " _required_ overall dimensions and
             | general form factor of an ATX power supply, " with or
             | without special airflow ducting (emphasis in original).
             | 
             | The linked PSU in the OP clearly does not meet this form
             | factor.
        
               | mook wrote:
               | ATX 2.2 spec seems to no longer have that; at least, the
               | PDF linked from the Wikipedia article on ATX doesn't.
               | 
               | Perhaps they removed it in a revision? That seems like a
               | silly idea...
        
           | vxNsr wrote:
           | This actually looks like a server psu.
        
         | rektide wrote:
         | I'd also point to Google's Little Box Challenge[1] as an
         | interesting data-point of yore.
         | 
         | Little Box Challenge went the other direction: instead of
         | taking AC and producing DC power, it was an inverter that took
         | DC power and produced AC output. It had to output 2kW and be
         | smaller than 655 cubic centimeters (cc's). The winning Red
         | Electrical Devil's team got 3x more dense than this[2]! 240
         | cc's! While inverting 2kW of juice. Second place was 340ccs.
         | 
         | I don't know whether we'd argue this DC->AC is harder/easier
         | than an ATX supply (AC->DC) (probably not?) but this was quite
         | an impressive competition, almost a decade ago, that resulted
         | in probably some of the most power-dense, highest-efficiency
         | power conversions that humanity has ever gotten up to. For
         | compare, this 250W unit is 212cc's. 8x less power conversion,
         | 88% the size.
         | 
         | The Little Box Challenge designs were published, so there's a
         | ton of great reading. Alas, Google frakking let the damned site
         | bitrot off the net?! Sooo, head to archive.org[3] to read the
         | team's writeups. From the winning CET Red Electric Devils
         | writeup:
         | 
         | > _GaN transistors have many very interesting electrical
         | characteristics (low Rds_on, low Qgate and Cds, ultra low Qrr);
         | these create technological advantages over current MOSFET and
         | IGBT devices (small size and low production costs).
         | Unfortunately, they also have serious drawbacks due to their
         | very fast switching characteristics: they are challenging to
         | drive and require sensitive electromagnetic noise management.
         | Another pitfall is the high voltage drop due to the reverse
         | current when the GaN is turned off. The solution selected to
         | overcome these difficulties is to control all the GaN
         | transistors using soft switching for the entire operation
         | range._
         | 
         | [1] https://news.ycombinator.com/item?id=8070215 (271 points, 8
         | years ago, 138 comments)
         | 
         | [2] https://ai.googleblog.com/2016/02/and-winner-of-1-million-
         | li...
         | 
         | [3]
         | http://web.archive.org/web/20171006105655/https://littleboxc...
        
           | elihu wrote:
           | I'm doing an EV conversion, and have trouble wrapping my head
           | around the idea that a motor controller that weighs about ten
           | pounds or so and isn't much bigger than a loaf of bread can
           | handle about 100 kilowatts of power, converting DC at around
           | 140-180 volts from the battery to 3-phase AC. And that's a
           | relatively low-end inverter.
        
             | virginiadoolf wrote:
             | the answer is liquid cooling. these Little Box and ATX
             | power supplies have to rely on passive cooling (radiative,
             | conductive, and convective) which is generally proportional
             | to surface area == physical size ^ 3. if you halve the
             | size, then, you lose 87.5% of the surface area! that's why
             | these things can't shrink as much. but ultimately the
             | silicon involved is miniscule.
        
               | elihu wrote:
               | Technically my motor controller can be passively cooled
               | too, it's just not recommended. (It automatically goes
               | into a low-power "limp" mode rather than burn itself
               | out.)
               | 
               | I'm not sure how much power it can handle continuously in
               | a pure passive-cooling mode.
        
               | wolrah wrote:
               | It would also be worth noting that a typical EV doesn't
               | have to run at anything close to 100% load for extended
               | periods of time.
               | 
               | What sort of power an electric drivetrain can handle for
               | a burst of acceleration lasting a few seconds versus what
               | that same drivetrain can handle as a continuous load are
               | two very different things.
               | 
               | The same even applies with combustion powered cars too,
               | if you look at the pickup truck market you'll see massive
               | power numbers on every manufacturer's diesel pickups. If
               | you look at their chassis-cab commercial trucks those
               | same diesel engines are often derated by 30-50% compared
               | to the pickups even while being equipped with larger
               | cooling systems. That's because the commercial variants
               | are rated to perform to spec all day every day where the
               | pickup version just needs to put a grin on the owner's
               | face when they floor it off the line and then
               | occasionally tow a boat or something.
        
           | chasil wrote:
           | The interesting thing about gallium nitride is its use in
           | blue LEDs (light-emitting diodes), which was discovered in
           | 1972 and perfected in 1993, resulting in a Nobel prize.
           | 
           | https://en.wikipedia.org/wiki/Light-emitting_diode#Blue_LED
           | 
           | I wonder what new engineering knowledge has emerged about
           | gallium nitride that allowed it to become such a recent force
           | in power supply electronics.
           | 
           | I didn't know that gallium nitride is transparent.
           | 
           | https://en.wikipedia.org/wiki/Gallium_nitride
        
             | Kirby64 wrote:
             | It's effectively process technology improvements that allow
             | gallium nitride devices to become less defect prone.
             | 
             | It's been known for some time that GaN has a superior
             | electron mobility number (which, effectively means you can
             | get a better/smaller/lower impedance/faster switching
             | device depending on which tradeoff you want). Problem is,
             | getting reasonably good process control has been
             | challenging. It appears some folks in the industry have
             | been overcoming that challenge, therefore we're seeing the
             | results of that.
        
           | Ballas wrote:
           | > I don't know whether we'd argue this DC->AC is
           | harder/easier than an ATX supply (AC->DC)
           | 
           | The little box challenge was significantly harder, primarily
           | due to the ripple requirements on the DC side. This is not an
           | issue in the same sense in the AC->DC case, because you don't
           | have that problem there (you have other ripple considerations
           | that might look similar, but are not (PFC and ripple on the
           | output)). Usually you would require a lot of capacitance to
           | solve the ripple issue for DC->AC and the winning team had a
           | very interesting way of solving it without the use of very
           | large capacitors.
        
           | brandmeyer wrote:
           | > I don't know whether we'd argue this DC->AC is
           | harder/easier than an ATX supply (AC->DC) (probably not?) but
           | this was quite an impressive competition, almost a decade
           | ago, that resulted in probably some of the most power-dense,
           | highest-efficiency power conversions that humanity has ever
           | gotten up to.
           | 
           | The LBC was misshapen because they had an odd requirement: Be
           | single-phase. A three-phase inverter (or rectifier) naturally
           | has low DC ripple and is both more compact and more efficient
           | than a single-phase inverter at all power levels. All of the
           | winning solutions had extra energy storage elements which
           | added inefficiency and bulk which a three-phase inverter
           | would not have needed.
           | 
           | With that in mind, the LBC was a little silly. A three-phase
           | machine at the same power level would have been much smaller
           | than any of the "winning" designs.
           | 
           | A high-efficiency ATX power supply has additional
           | requirements that the LBC didn't need to meet: Isolation.
           | This implies the use of a transformer to protect the low-
           | voltage DC side from the AC side. They typically accomplish
           | this by rectifing AC, using a transformer-isolated
           | unidirectionally optimized DC/DC supply to 12V, and then
           | provide a handful of lower-power DC/DC converters to derive
           | the other voltage levels used by ATX. A modern unisolated
           | DC->AC machine is effectively symmetric in its power flow,
           | and also functions as an AC->DC machine.
        
             | spookthesunset wrote:
             | One of the things I only recently learned is modern power
             | supply's aren't using the transformer to knock down "raw
             | mains" 60hz AC. Modern switch mode PSU's in-fact rectify
             | the AC to DC and then chop it up at a much higher
             | frequency.
             | 
             | By using a higher frequency, the transformer can be much
             | smaller and more efficient. If they were doing mains 60hz
             | AC the transformer would be substantially larger.
             | 
             | I forget if they also step the supply side DC voltage up
             | too...
        
               | brandmeyer wrote:
               | > I forget if they also step the supply side DC voltage
               | up too...
               | 
               | They do, but they don't have to. The front-end rectifier
               | boosts the voltage up to 400-450 VDC. This way, most of
               | the components can be optimized for a single world-wide
               | compatible machine that is capable of rectifying 230VAC.
               | 
               | In principle, you could squeeze out a bit of efficiency
               | (or cost) by producing a North American market machine
               | that was optimized for 120V and a separate machine
               | optimized for 208/230V. In practice, supply chain
               | simplification reduces overall per-unit costs, so just
               | about everything is designed as a single machine for
               | world-wide markets. Only the plugs change. For ATX, only
               | the cord shipping in the box changes.
        
         | NavinF wrote:
         | > this 250W unit is 170x50x25
         | 
         | They've been selling a 400W (still fanless!) DC-DC version for
         | years and it's only 160x51.5x26mm :
         | https://hdplex.com/hdplex-400w-hi-fi-dc-atx-power-supply-16v...
         | 
         | I use it to power my CPU+mobo but I also have a couple of
         | server PSUs further away to power my 3090 over several pairs of
         | THNN. It's far from a SFF build, but it can be totally silent.
        
           | morganvachon wrote:
           | The difference is that this unit does the AC-DC conversion
           | inside itself, whereas your DC-DC power supply relies on an
           | external AC-DC brick that is likely the same size as this
           | entire self contained unit, if not larger.
        
             | bombcar wrote:
             | If you're dealing with solar or a vehicle you may already
             | have DC available; too bad it can't take -48v which some
             | racks still supply.
        
           | dwild wrote:
           | To be a fair comparison would need to include the AC-DC power
           | supply that you keep outside to power that thing... it's
           | double the size once you account for that.
        
         | _delirium wrote:
         | I've found high-wattage USB-C chargers to have very poor
         | reliability. All the 18-W chargers I've owned have lasted
         | multiple years, but the compact 90-W+ chargers have a lifespan
         | measured in months.
         | 
         | Of course, they all purport to offer a warranty, but if you try
         | to claim, they will not honor it. They will claim it's because
         | you bought from Amazon and they don't warrant Amazon purchases
         | (despite this being their main retail outlet, and the fact that
         | they advertised the warranty IN the Amazon sales materials). Or
         | something similar.
        
           | pugz wrote:
           | What brands have you used? My Apple 96W USB-C charger is
           | still doing fine after having it for just under two years
           | now.
        
             | solarkraft wrote:
             | Apple cares about its brand. Chinese no name vendors don't
             | at all, it's horrifying what plain illegal corner-cutting
             | they often engage in. But that's of course what they're
             | rewarded for.
        
               | bombcar wrote:
               | In fact, if you're in a bind and need a USB C charger
               | that will work reliably, you may want to pay the cost to
               | get a genuine Apple one. (I won't order Apple chargers
               | from Amazon; I get them direct from Apple or a real
               | retailer because I don't trust the co-mingling).
               | 
               | Some of the power-tool brands are beginning to make USB-C
               | devices, those chargers should be reliable also. Here's
               | Dewalt: https://www.dewalt.com/product/dcb094k/usb-
               | charging-kit
        
           | torginus wrote:
           | I agree - I wonder why Chinese junk that basically barely
           | works and not for long even then has managed to establish
           | such a strong foothold on the retail market (particularly
           | Amazon). I had the same experience - moreover my charger had
           | multiple ports, but as soon as you plugged more than one
           | thing into it, the wattage would drop drastically. my 100W
           | charger would do 30W on port 1 and 10W on port 2. And that
           | was the optimal case - more often than not, using more than
           | one port would make devices randomly disconnect.
        
             | scotty79 wrote:
             | Be happy the wattage dropped. When I connected 2 fast
             | charging devices my charger just fried.
        
             | solarkraft wrote:
             | It's cheap and there's little responsibility for selling
             | crap. Amazon is the only site I'm aware of where you can
             | actually somewhat judge the quality of a product through
             | reviews, and those too are often dodgy as hell. Otherwise
             | it's all just the same fake pictures and outright lies
             | about specs. And nobody cares because _it 's cheap_.
             | 
             | Companies selling under brands want a premium for them
             | (Anker, Aukey) and "no name brands" you can actually put a
             | little confidence into (Ugreen, Blitzwolf) are, for some
             | reason, rare.
        
             | ncmncm wrote:
             | I just had a 4-port USB brick burst into flame. It
             | certainly would have burned down the house if I had not
             | happened to be in the room. It had sat untouched for an
             | hour before the event.
        
               | Tijdreiziger wrote:
               | Wow, what brand?
        
               | torginus wrote:
               | These brands are like the ship of Theseus - you'll never
               | get the same thing twice.
        
               | bombcar wrote:
               | Better than the brand is the picture of the device
               | (before fire, hopefully) as all the yumcha brands off of
               | Alibaba will usually keep the exact same physical
               | characteristics.
        
             | tjoff wrote:
             | That isn't so surprising nor uncommon even among high-end
             | chargers. Many multiple-port chargers can only generate one
             | voltage other than 5V.
             | 
             | So, you charge your laptop at 100W means 20V*5A, then
             | connect a phone that can only negotiate to 9V. Now your
             | laptop can, at best, only get 45W. But laptop and phone
             | might also have to share the same 5A, meaning something
             | close to what you described. (or, your laptop might not
             | support 9V ... in which case I'd guess one of the devices
             | would disconnect?)
             | 
             | You might be better off using a USB-A port if the charger
             | has one, then your laptop could perhaps remain at ~100W and
             | your phone might still get ~10W. (Assuming charger and
             | phone doesn't also have quickcharge which might complicate
             | it further). Or, perhaps charge your phone via your laptop
             | (yes, negates the point of a multiple-port charger, but if
             | you are in hurry - otherwise, slow charging is preferably
             | anyway)
             | 
             | A good review will test this, and a good product page will
             | specify this (but if your are not looking/thinking about it
             | it is easy to miss).
        
           | solarkraft wrote:
           | I have had a couple of pretty cheap high wattage USB bricks
           | for years (5-6 or so at this point) and none of them have
           | died on me so far. Props to Ugreen, I guess!
        
           | Youden wrote:
           | I think you might be unlucky or buying low-quality models. I
           | have a 100W Minix NEO P2 that was one of the first GaN
           | chargers available near me and it's still going strong 2
           | years later.
           | 
           | I also have a 60W Satechi travel charger that's been powered-
           | on 24/7 for 3 years now without the slightest hint of a
           | problem. It's even been buried under cushions for hours at a
           | time.
           | 
           | The only charger I've had actually die was a Hama-branded
           | device. Hama is the cheapest possible Chinese junk the brand
           | can find.
        
           | SkyPuncher wrote:
           | I have an Anker GAN power block that's working extremely
           | well.
        
           | lrem wrote:
           | My two Minix P2s had no issues over 1.5 years.
        
           | rektide wrote:
           | I have a ravpower, a hyper, and just bought the new ugreen.
           | The ugreen is too new to judge, but the others have ran for
           | over two years, and a good amount of that time has been
           | outdoors in the sun.
           | 
           | I constantly expect failures. This seems like an absurd task
           | I'm putting them up to. But they are all still alive & doing
           | the job.
           | 
           | I've had a kill-a-watt so I can see their power consumption.
           | A large amount of their life is spent ~60 watts, but there's
           | definitely hours on end & heavy usage days, where they go up
           | to or stay at 90+.
           | 
           | My anecdotal data looks different than yours.
        
             | _delirium wrote:
             | My Ravpower device died within 8 months, and they refused
             | to honor the warranty, giving as the reason that the
             | purchaser of record was Amazon LLC, not Ravpower. Even
             | though they advertised a warranty on their Amazon page,
             | which was the main way they sold the devices.
        
               | gorbypark wrote:
               | Does Amazon not honour the warrenty in that case? I've
               | never had to deal with a similar situation but I kind of
               | figured that Amazon would do something if the page
               | advertised a warranty and the company refuses to honour
               | it.
        
               | AshamedCaptain wrote:
               | I have never been able to get Amazon to honor a warranty
               | when the manufacturer refused, even though the law in my
               | country clearly says the retailer is responsible in the
               | first place. In fact the button to return a product
               | disappears from the order after a couple months, and they
               | don't even have a category in their support system for
               | this.
        
               | ThePowerOfFuet wrote:
               | Talk to Amazon customer service and tell them you'd like
               | to make a claim pursuant to consumer rights law.
        
               | thathndude wrote:
               | I smell a class action.
        
               | retcon wrote:
               | ... dreams of the EPA obtaining warrants for the fraud on
               | the public for the disposal costs of so much wasted
               | electronics...
        
               | londons_explore wrote:
               | In the EU you get 2 years warranty for all items from
               | every retailer by law, and most generally honour them.
        
               | gambiting wrote:
               | So this is a very frequently repeated misconception about
               | what the EU law actually says.
               | 
               | Yes, there is an EU law that says retailers are
               | responsible for 2 years(6 in a some cases) for any item
               | they sold......but only to rectify any manufacturing
               | defects. The law additionally states that any defect
               | found in the first 6 months is presumed to be a
               | manufacturing issue, anything after the first 6 months
               | it's the responsibility of the _customer_ to prove that
               | the product has failed due to a manufacturing problem. I
               | 'm sure you can appreciate that this can be very hard to
               | do.
               | 
               | It's not a "warranty" in the sense that most people mean
               | warranty. If your laptop fails 18 months after purchase,
               | the retailer only has to fix it if _you_ can prove that
               | it failed due to a manufacturing defect. It 's different
               | to manufactuer's warranty, which usually covers _any_
               | defect no matter the reason.
               | 
               | And yes, there is also the law that states that products
               | should last a "reasonable" amount of time - but what is
               | reasonable is not a strict definition, and again,
               | unfortunately sometimes has to be argued in small claims
               | court. It's not so straigtforward.
        
               | tinus_hn wrote:
               | These are not EU laws, they are EU directives directing
               | the member countries to implement laws. But these laws
               | are not all the same, for instance in how much effort a
               | customer has to make to 'prove' that a device failed due
               | to a manufacturing defect.
        
               | danieldk wrote:
               | However, in practice most good retailers do not make a
               | big deal out of the burden of proof as long as there is
               | no visible damage that could cause the issues.
               | 
               | I have used warranty frequently after 6 months and never
               | had to prove it is a manufacturing defect. Of course, if
               | you buy at some shady webstore or known-bad retailer, you
               | might have more issues.
        
           | adrianN wrote:
           | If you bought the device off Amazon, I believe Amazon should
           | be your point of contact for warranty claims.
        
       | londons_explore wrote:
       | This supply goes to quite some effort to have a good power factor
       | and filter harmonics sent to the grid... But why?
       | 
       | Grid operators typically have laws in place saying how many
       | harmonics you're allowed to inject, and for stuff under a few
       | kilowatts it's totally fine to just have a bridge rectifier
       | straight to a capacitor. That's what every other electronic
       | device in your house will do.
       | 
       | If you're making a high efficiency power supply, you'd probably
       | want that to be a synchronous rectifier to get 1% or so more
       | efficiency, but it would still only be drawing current on the
       | peaks of the sine wave.
       | 
       | But I don't see why you'd want to go to much effort to make your
       | current draw a nice sine wave rather than a series of peak-
       | chopping spikes. Is it to save money on copper in the power
       | supply wire perhaps?
        
         | formerly_proven wrote:
         | > and for stuff under a few kilowatts it's totally fine to just
         | have a bridge rectifier straight to a capacitor. That's what
         | every other electronic device in your house will do.
         | 
         | The EMC Directive mandates compliance with IEC 61000-3-2 which
         | certainly requires you to do a little bit more than hook up a
         | bridge rectifier to the grid.
        
       | aasasd wrote:
       | Difficult to imagine the size from a photo with a phone (maybe
       | it's due to me being a user of Android, idk). I'd prefer to see
       | it next to previous small power supplies--because I'm vaguely
       | sure I've seen some of comparable size and wattage for NASes, and
       | my shopping for them was ten years ago. However, this one is
       | likely considerably slimmer in height.
        
         | hnuser123456 wrote:
         | 1x2x7 inches
        
         | kraftman wrote:
         | Theres a comparison here vs other standard PSU sizes:
         | https://hdplex.com/pub/media/image/Product/250WGaN/overview/...
        
           | aasasd wrote:
           | Ah, indeed I should've taken a look at the manufacturer site.
           | However, I'm pretty sure that there is a format narrower than
           | FlexATX from the picture -- because I was thinking of buying
           | a PSU like that for a petite NAS. (Until I learned that there
           | are small, silent and cool external PSUs, similar to ones for
           | laptops.)
        
       | ericbarrett wrote:
       | 94% efficient! When I started building PCs it was common to see
       | 60-75% if you weren't inside a very narrow window of optimum
       | load. It's mind-blowing how efficient electronics have become.
       | 
       | Also < 0.4W idle. Wow.
        
         | zokier wrote:
         | "80 Plus Gold" rating already required up to 92% efficiency, so
         | 94% isn't that groundbreaking. Here is one random example from
         | 5y ago that hits 94-96% efficiency
         | https://www.anandtech.com/show/11252/the-seasonic-prime-tita...
        
           | ericbarrett wrote:
           | I disagree, 92 -> 94% is a 25% reduction in waste!
        
             | magicalhippo wrote:
             | At 100W load, it's a 2.3W reduction is waste. If it's on
             | 24/7 that's about 20kWh over a year, or just shy of
             | charging my old Nissan Leaf once.
             | 
             | Then again, 20kWh here, 20kWh there, it adds up.
        
       | nimish wrote:
       | Could be denser. Instead of a big passive EMI filter, use an
       | active one (noise cancelling, essentially).
       | 
       | It's a little baffling why they aren't more widely used, they
       | aren't that complicated.
       | https://u.dianyuan.com/bbs/u/17/1086016427.pdf is an example.
       | It's almost comically simple: connect a current sensor, a high-
       | pass filter, and an opamp controlling a transistor. With some
       | thought it could probably be cut down even more.
       | 
       | I think TI has integrated this into their controllers already.
        
         | ClumsyPilot wrote:
         | Is the passive one more reliable, less to go wrong?
        
           | [deleted]
        
           | nimish wrote:
           | Well the big electrolytic caps you need for the passive
           | filters are infamously unreliable which is why you see
           | everyone trumpeting their "Japanese" brand capacitors which
           | are supposed to be better.
           | 
           | The caps you need for the active filter are the tiny solid
           | ceramic ones that are basically bulletproof except in high
           | vibration environments. The ICs needed are similar.
        
         | hoseja wrote:
         | Consumer electronics are just so hilariously bleak. Why use the
         | smart option when a cheap one almost does the job too? That
         | would be _overengineering_ and everyone can do that! Only the
         | smartest engineers know how to deliver maximum value to
         | shareholders while offloading the maximum possible
         | externalities!
         | 
         | Sorry, pet peeve of mine.
        
           | nimish wrote:
           | Yeah it's really disappointing that even in high cost
           | consumer electronics there's very little incentive to
           | innovate in non-sexy areas :(
        
       | Dunedan wrote:
       | The website of the manufacturer provides more information and
       | more photos: https://hdplex.com/hdplex-fanless-250w-gan-aio-atx-
       | psu.html
        
       | [deleted]
        
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       (page generated 2022-05-27 23:02 UTC)