[HN Gopher] New 2GB Raspberry Pi 5 has 33% smaller die, 30% idle...
       ___________________________________________________________________
        
       New 2GB Raspberry Pi 5 has 33% smaller die, 30% idle power savings
        
       Author : ingve
       Score  : 188 points
       Date   : 2024-08-29 15:54 UTC (7 hours ago)
        
 (HTM) web link (www.jeffgeerling.com)
 (TXT) w3m dump (www.jeffgeerling.com)
        
       | GGO wrote:
       | is there going to be D0 stepping for the 8GB version?
        
         | jsheard wrote:
         | I don't see why there wouldn't be, it's cheaper to manufacture
         | with seemingly no downsides. They probably won't revise the 4GB
         | and 8GB versions until their stocks of the original stepping
         | are used up though, and once they do introduce revised versions
         | it may be a lottery which version you get for a while.
        
           | AstroJetson wrote:
           | I'll bet they just slipstream them in. There was a huge
           | backlog of the 8GB, that now looks pretty much cleared out.
           | So it could be awhile before the D0 show up.
        
         | hajile wrote:
         | TSMC charged just a hair under $4000 per 16nm wafer in 2020.
         | 
         | Wafer calculators at 0.2 defect/cm2 on a 300mm wafer gives 950
         | fully-good dies out of 1061 for the old die (~89% good) and
         | 1469 fully-good dies out of 1584 (~93%) for the new dies.
         | 
         | Dividing that out gives $4.21/chip for the old chip and
         | $2.72/chip for the new chip. At $80 for an 8gb board, that
         | represents a ~1.9% increase in profit per board. For the $60
         | 4gb version, it's more like 2.5% increase in profit per board.
         | 
         | In real-world terms, if they sell 10M Pi5 units with the new
         | chip, they'll have an extra $15M in the bank in saved
         | production costs alone (minus whatever costs to strip
         | everything out and tape out again). Furthermore, the new chip
         | gets cheaper with every chip they make as the R&D costs get
         | more and more diluted.
        
       | rjsw wrote:
       | You had speculated in a previous thread that the new die could
       | result in power savings, good to see some real measurements.
        
       | toastau wrote:
       | Nice work!
        
       | 0cf8612b2e1e wrote:
       | Some of the power savings could be chalked up to less RAM,
       | because more RAM requires more power. But that doesn't explain
       | all the results.
       | 
       | Is there a calculation to estimate RAM power consumption? I keep
       | wanting to get a low powered N100, and have been wondering if I
       | use say 8 vs 16GB RAM, would that make a measurable power
       | difference?
        
         | Mistletoe wrote:
         | A small amount.
         | 
         | > As a rule of thumb, you can expect to allocate around 3 watts
         | of power for every 8GB of DDR3 or DDR4 memory.
        
           | 0cf8612b2e1e wrote:
           | Similar for DDR5?
           | 
           | In the context of a N100, 3W is actually pretty high. Many of
           | these systems idle around 10W.
        
             | flyingpenguin wrote:
             | Yeah but unless you are deploying a bunch of them, its only
             | like $3/year each
        
             | snovv_crash wrote:
             | That's why many laptops run LPDDR these days.
        
             | spockz wrote:
             | My N100 from minisforum runs on 3.6W idle with 4-8W for
             | medium to high cpu usage to 20W on full load with SSD, CPU,
             | and integrated encoder loaded.
             | 
             | It is way more powerful than a pi and in low power mode as
             | efficient.
        
               | fswd wrote:
               | I probably have the same N100 miniforums and can only get
               | it down to 7w. Is it possible you could share how you got
               | it down to 3.6W and 4-8W?
               | 
               | I just got this N100 a few weeks ago, have it on a
               | killawatt next to my desk.
        
               | spockz wrote:
               | There are many tips here: https://gathering.tweakers.net/
               | forum/list_messages/2096876 but I think the thing that
               | did the trick was simply `powertop ---auto-tune`. I also
               | disabled the wifi in the bios. I ran for a bit with turbo
               | disabled which lowered the consumption a tiny bit and
               | severely limited the peak usage, but it also made the
               | system slow overall. So I enabled it again and now
               | sometimes usage spikes but feels snappy. I'm running
               | Fedora.
        
           | mallets wrote:
           | That's a ridiculous amount of power, is that answer from a
           | LLM? It's in the range of ~150mW for LPDDR4. Around half that
           | in idle.
        
             | hnuser123456 wrote:
             | You specified LP, they didn't.
        
               | mallets wrote:
               | It doesn't matter too much whether it's LP or not for
               | idle, around 20% more at worst. It's at full BW util
               | where it's close to double power consumption. That would
               | still put it at less than half watt for full load.
               | 
               | Look for "AM62x Power Consumption" app note, page 5.
        
           | adgjlsfhk1 wrote:
           | https://www.servethehome.com/ddr4-dimms-system-power-
           | consump... which is the only source I've seen that looks even
           | vaguely trustworthy gives 2 watts per 8 gb of ddr4 (and ddr5
           | should be about 10% lower since it drops to 1.1 from 1.2
           | volts assuming similar amounts of current).
        
         | hajile wrote:
         | Their numbers seem to indicate that Pi disabled parts of the
         | chip in firmware instead of physically lasering them out. This
         | leaves those parts still leaking some current and explains the
         | power difference.
        
         | moffkalast wrote:
         | > 8 vs 16GB RAM, would that make a measurable power difference?
         | 
         | I think the short answer is.. it depends. Current draw depends
         | on usage, supposedly from 10% at idle up to full when doing
         | massive read/writes. But it should be in the two to three digit
         | miliwatt range which isn't much compared to the N100 itself
         | which pulls 6W at idle, being an inefficient x86 space heater.
         | 
         | The Pi 4 4GB can idle at 1W using LPDDR4, the Pi 5 8GB using
         | 50% more efficient LPDDR4x idles at... 3W. Meanwhile the
         | average 12GB LPDDR5X Android phone can idle a whole week on a
         | tiny 1 cell lipo (with power saving mode on), making this look
         | so bad it's actually funny.
         | 
         | The long standing problem with Pi Foundation products is a
         | complete disregard for any low power states, sleep or
         | hibernation, so they probably don't do any RAM related power
         | optimization either. It's only now with the RP2350 that they've
         | finally implemented some kind of working sleep mode for the
         | very first time in anything at all.
        
           | Marsymars wrote:
           | > N100 itself which pulls 6W at idle
           | 
           | That's not right - my entire N305 system takes 4-5W at idle.
        
             | moffkalast wrote:
             | Fair point, N100 systems do differ quite a bit generally,
             | the numbers I've got in my head are what I've seen people
             | quote for the Radxa X4 recently. Some might be more, some
             | less.
        
       | quaintdev wrote:
       | Genuine question what is the use case for such configuration I
       | mean less RAM and powerful CPU?
       | 
       | I use my Pi for self hosting so I need more memory and more CPU
       | is always better for my case. If they need less power consumption
       | then they could have used Pi 4 or other lower version.
       | 
       | Besides low cost I don't see other advantage of such
       | configuration. Please enlighten me.
        
         | mlyle wrote:
         | Pi 5's peak consumption is higher, but if you are doing the
         | same amount of computational work (but a bit above idle) it is
         | less.
         | 
         | Now this uses even less, and even the idle powers are
         | comparable to 4. This wins in every way over Pi4, except cost.
        
           | tonymet wrote:
           | Given people typically use these for a home server or
           | embedded controller, who cares about saving a couple watts?
           | 
           | 1 watt savings idle? .72 kwh a month? in my area that's about
           | 5[?] , even in california that's 40[?] / month / device ?
           | 
           | Are 1000-instance Pi arrays common? i can think of 100 better
           | ways to get that amount of computing resources.
        
             | byteknight wrote:
             | I think you are applying your usecase and thinking that is
             | everyone's use case. Think battery power.
        
               | mlyle wrote:
               | Yup. I had students running a machine learning model on a
               | Pi attached to a scooter. The power draw of the computing
               | system was significant, and the performance limitations
               | were too.
               | 
               | The existence of commodity, well-documented, well-
               | supported SBCs offering more computing in less power is
               | exciting.
               | 
               | (Also, using less power means you can put it in more
               | places without worrying about getting rid of the heat, or
               | can go longer before throttling).
        
               | tonymet wrote:
               | as in portable or embedded? Embedded, Pi has too much
               | consumption. saving a watt isn't your problem
        
         | Aachen wrote:
         | If your needs are greater than a Pi but not at the level where
         | you want to be buying professional server hardware, I can
         | recommend checking if you or a family member still has a laptop
         | they're not using anymore. Free hardware that would otherwise
         | end up going to waste, and anything that had good performance
         | in 2012 is still faster than a new Pi today. The older, the
         | more likely it is to have replaceable RAM so you can stick in
         | 16GB easily (older RAM types are also cheaper)
        
         | Max-q wrote:
         | Maybe real time image processing from a camera. 2GB would
         | probably be more than enough, and less power draw is nice when
         | running continuously.
        
         | justin66 wrote:
         | For an embedded application involving signage or a kiosk, 2GB
         | is probably plenty, and if you're doing enough of them the
         | money saved would be worth it.
         | 
         | For a home user with one, or only a handful of, machines I
         | don't think you'd necessarily need to save a few bucks this
         | way. Although _people obsessing over pennies_ is a theme in
         | most Raspberry Pi threads, so there is clearly appeal for some.
        
         | georgeecollins wrote:
         | I don't know if this configuration works for me, but unlike a
         | lot of people here I have used Raspberry Pi's in robots. The
         | 5's power consumption is such that it is a problem. The jensen
         | nano is no longer supported. So maybe there is a "thingaverse"
         | need for something more powerful then a pico /arduino but not
         | so power hungry.
        
         | suprjami wrote:
         | Broadcom pushed the old Raspberry Pi SoC architecture as far as
         | it would go, but it's hard limited to 1Gb RAM.
         | 
         | Raspberry Pi has become a development platform for Broadcom
         | SoC, so they can sell the same chip in their corporate products
         | and the cost of development is partially covered by Pi sales.
         | 
         | They also have an educational non-profit organisation, but
         | don't mistake the Raspberry Pi for a 100% selfless endeavour.
         | 
         | Broadcom have been very hostile at taking Pi clones of the
         | market. Look at that happened to ODroid's Zero clone with the
         | same SoC as the Zero.
        
       | PedroBatista wrote:
       | More memory also needs more power.
       | 
       | Not sure what percentage of those gains can be attributed to less
       | memory and what can is due to better die/process.
        
       | kobieps wrote:
       | Is the firmware still closed source?
        
         | written-beyond wrote:
         | They've improved a lot, it's mostly the broadcom graphics
         | firmware that still requires blobs. Probably because they've
         | licensed the IP from somewhere else and the effort to reward
         | ratio is too low.
        
           | mort96 wrote:
           | In other words: yes, the firmware is still closed source.
        
         | autoexec wrote:
         | I wouldn't mind them not using open firmware as much if we had
         | unofficial alternatives that worked without sacrificing
         | functionality, but I don't think anyone has managed that even
         | after all this time.
        
       | alxjsn wrote:
       | I rather just buy used Lenovo Thinkcentere PCs on eBay. Way more
       | power, cheaper and relatively small. There's a lot of different
       | CPU/RAM/DISK configurations you can find.
       | 
       | I've been buying these, throwing Fedora IoT, docker, and
       | Tailscale on them and running them from different locations for
       | personal projects.
        
         | PedroBatista wrote:
         | Sure, if you need a machine to do "normal" PC/server things,
         | buying a computer would be the natural path.
        
         | geerlingguy wrote:
         | There's also the Radxa X4 -- Pi 4/5 form factor (tiny bit
         | larger but not substantial), has a PoE HAT available, has
         | 40-pin GPIO (with caveats, but it's basically a Pico strapped
         | on the same board), and the N100's built-in GPU can run circles
         | around the Pi or even RK3588 boards.
         | 
         | The efficiency isn't there, and you'll need to figure out a
         | better cooling/case solution than the one Radxa ships, but I'm
         | impressed by this little board.
         | 
         | If you can stretch your budget past $100 you can get a good
         | brand new N100 or N305 system that will go further. Used gear
         | is fine, but the power efficiency for anything in the $50-80
         | range used is pretty rough. Some people don't worry much about
         | that, but in some parts of the world it can be $5+/month more
         | to run older machines!
        
           | throwup238 wrote:
           | _> Some people don 't worry much about that, but in some
           | parts of the world it can be $5+/month more to run older
           | machines!_
           | 
           | California being one of the worst offenders, ironically. In
           | SoCal my family and I pay (across several households) between
           | $0.50/kWh and $0.99/kWh, so even a 15W idle can cost us at
           | least $5 a month.
        
         | bri3d wrote:
         | A few notes (as someone who is pretty staunchly anti-Pi-as-a-
         | server, I end up having this debate often, and I do think there
         | are reasons to do both):
         | 
         | * A Pi will sit much lower in total power consumption than
         | almost any used PCs if both are doing effectively nothing (ie -
         | simple, spiky tasks like filtering DNS, serving static content
         | from RAM, etc.). You need to be doing something with the system
         | before a PC server comes out ahead, and most people using a Pi
         | as a home server... aren't.
         | 
         | Compared to a modern low-power x86 PC system, the difference
         | isn't meaningful, but if you're buying used stuff 3 generations
         | back, the difference becomes somewhat meaningful in terms of
         | electric cost (on the order of tens of dollars per year, which
         | is significant for hardware which cost tens of dollars to start
         | with).
         | 
         | * The Pi of course has GPIO, SPI, etc. exposed, so you can use
         | it as a nice "hybrid-IoT" device where it's a home server _and_
         | a sensor aggregator, for example. And the hat ecosystem, while
         | generally insanely overpriced, is convenient.
         | 
         | Now, the moment you're running K8s/Docker or a real compute
         | workload (security camera image recognition, etc.) you should
         | probably move off of the Pi and onto something nicer, indeed. I
         | absolutely never understood people running clusters of Pis or
         | those goofy multi-Pi carrier boards. Just buy a real PC.
        
           | Aachen wrote:
           | > A Pi will sit much lower in total power consumption than
           | almost any used PC
           | 
           | For electricity consumption, beyond the wallet, it actually
           | seems that hardware should have a lifespan on the order of
           | decades before electricity consumption savings offset the
           | environmental impact:
           | 
           | "For laptops and similar computers, manufacturing,
           | distribution and disposal account for 52% of their Global
           | Warming Potential (i.e. the amount of CO2-equivalent
           | emissions caused). For mobile phones, this is 72%. The report
           | calculates that the lifetime of these devices should be at
           | least 25 years to limit their Global Warming Potential."
           | --https://wimvanderbauwhede.codeberg.page/articles/frugal-
           | comp...
           | 
           | Rather than buying a new Pi, repurposing a 5-year-old laptop
           | has advantages if this something one cares about. Desktops
           | are quite a bit more hungry (I've heard this got better in
           | recent years), but I can attest that a 2012 laptop still
           | functions very well as a server, easily better than a
           | 2024-era Pi. Probably I'll replace it in the next 2-4 years
           | (so at ~15yo) when my current laptop finally will have given
           | me enough grief (my inner grandpa complains they don't make
           | 'em like they used to), and I'm not saying others must
           | optimise for climate alone either, but it's something to
           | consider when deciding on a good balance
        
             | k_bx wrote:
             | Environmental impact is not the main concern when it comes
             | to power consumption. Main concern is how long will it work
             | on a battery before a maintenance person can come by and
             | switch the battery or if the sun will come out and start
             | charging it again.
        
           | sofixa wrote:
           | > I absolutely never understood people running clusters of
           | Pis or those goofy multi-Pi carrier boards. Just buy a real
           | PC.
           | 
           | A bunch of Pis allow you to run multi-node clusters on the
           | cheap. If you're just experimenting with
           | Kubernetes/Nomad/whatever, you don't need a lot of resources,
           | just multiple nodes. It's easier and depending on config
           | potentially cheaper than getting a beefier mini PC, throwing
           | lots of RAM, and running VMs.
        
           | AshamedCaptain wrote:
           | > * A Pi will sit much lower in total power consumption than
           | almost any used PCs if both are doing effectively nothing (ie
           | - simple, spiky tasks like filtering DNS, serving static
           | content from RAM, etc.). You need to be doing something with
           | the system before a PC server comes out ahead, and most
           | people using a Pi as a home server... aren't.
           | 
           | That's not necessarily true since the Pis are particularly
           | terrible at idle power consumption. E.g. the "power off"
           | state consumption shown in the article is actually higher
           | than the idle consumption of some low-power Atom/Celeron x86
           | chips. The Pi is just terrible at power management.
        
             | suprjami wrote:
             | Citation needed?
             | 
             | Pi 2 and 3 typically sit at 200 mAh and 230 mAh, Pi 4 is
             | not far away. Zero 2W can go down to 96 mAh.
             | 
             | https://www.jeffgeerling.com/blogs/jeff-
             | geerling/raspberry-p...
             | 
             | https://www.jeffgeerling.com/blog/2021/disabling-cores-
             | reduc...
             | 
             | I don't see any x86 system approaching those numbers.
        
           | supertrope wrote:
           | To illustrate a Lenovo Thinkcentre m720s idles at 9W! Intel
           | i5-8500 (6C/6T), 8GB DDR4, 256GB NVMe SSD. It cost $120.
        
             | ssl-3 wrote:
             | In order to begin to make a valid price comparison to this
             | used (ie, not new) PC, we'd also need to know how much a
             | used Raspberry Pi system would cost.
        
               | supertrope wrote:
               | Go to ebay.com. Search for Raspberry Pi 5 or 4. See
               | actual market prices by filtering to sold listings. Add
               | cost of case, power supply, storage, maybe even active
               | cooler.
        
         | jchw wrote:
         | Emphasis on way more _power_. Granted, power draw isn 't a huge
         | problem for price reasons, since the cost of electricity is
         | _usually_ not that huge of a factor, but if you wind up running
         | a lot of these, it can add up. More power draw is also a
         | detriment if you want to keep things lean for longer battery,
         | which makes me hesitant to put many older stock computers in
         | the critical path of my network.
         | 
         | Don't get me wrong, though. Old stock computers are excellent
         | for a wide variety of tasks, it's just that they definitely
         | don't encroach on a lot of the use cases of modern SBCs. You
         | needn't buy a Raspberry Pi 5 either; plenty of use cases like
         | Home Assistant will run pretty well on a Pi 4 or even a Pi 3,
         | and that's not getting into the many other reasons why a Pi may
         | be interesting (like HATs, being able to use PoE power, GPIO,
         | or even just the I/O in general.)
        
         | autoexec wrote:
         | I can't bring myself to buy Lenovo anything since they've
         | repeatedly shipped products infested with malware, sometimes
         | doing it in exchange for money. Once a company sinks that low
         | and treats users with such disrespect I don't know how or why
         | they should be trusted again.
        
           | gosub100 wrote:
           | I tried buying a used one on eBay and was disappointed to
           | find it used a proprietary SATA power cable or connector,I
           | can't recall. I hope they stopped doing that.
        
           | sgt wrote:
           | The ThinkCentres kinda look like "evil" IBM corporate
           | machines out of a Star Wars movie. I wish I could put an IBM
           | logo on mine to complete the picture.
        
         | sgt wrote:
         | I just bought one! It's brilliant, I had no idea. Cost almost
         | nothing, and I removed the HDD and put an SSD in there, extra
         | RAM and it's lightning quick.
         | 
         | Right now I have Windows 10 on it as I needed to run some old
         | proprietary software, but it's a proper gem of a machine. I got
         | the one without touch screen.
        
         | iwontberude wrote:
         | Have 13 of them and I love them
        
         | Rebelgecko wrote:
         | What's the break even point for the way more power vs the
         | cheaper upfront cost? My raspberry pi has probably saved
         | hundreds of dollars over the years in electricity vs what I'd
         | have spent running a cheap Intel box
        
       | pseudosavant wrote:
       | If they are using a standard 300mm wafer and have similar yields,
       | the D0 stepping will allow them to get ~50% more chips per wafer
       | than the C1 stepping.
        
       | hcfman wrote:
       | Nice comparison. Looking forward to the 4nm version
        
       ___________________________________________________________________
       (page generated 2024-08-29 23:01 UTC)