[HN Gopher] BGA socket allows RAM upgrades on SBCs
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       BGA socket allows RAM upgrades on SBCs
        
       Author : zdw
       Score  : 21 points
       Date   : 2022-04-21 14:49 UTC (3 days ago)
        
 (HTM) web link (www.cnx-software.com)
 (TXT) w3m dump (www.cnx-software.com)
        
       | Syonyk wrote:
       | > _While it looks neat, I'm not convinced we'll see barebone
       | single board computers where users can insert their own eMMC
       | flash and RAM any time soon, since it would likely add to the
       | overall costs. A more likely use would be for board vendors
       | wanting to test RAM chips from various vendors and of different
       | capacities._
       | 
       | Most SBCs use socketed eMMC chips available in various
       | capacities. Pine64 and Odroid's eMMCs are compatible, at least,
       | and live on a tiny little board you can swap out.
       | 
       | I don't see the cost and complexity as being worth it, though.
       | Just stuff the things full of RAM, have lower capacity options,
       | and solder it - same as we see today. Yes, it's nice on paper to
       | swap the RAM out, but I guarantee these sockets aren't cheap, and
       | for something that's used once or twice, eh. Not worth the
       | hassle...
       | 
       | I like things that are easily repaired, but I also don't see a
       | huge wave of ARM SBC RAM failures. They're already repairable, it
       | just requires hot air rework and a bit more skill than swapping a
       | DIMM.
        
         | ClumsyPilot wrote:
         | "They're already repairable, it just requires hot air rework
         | and a bit more skill than swapping a DIMM."
         | 
         | Where do I find people who can do that?
         | 
         | I google 'electronics repair London' and all I get are little
         | shops where a dude with a screwdriver might replace a RAM
         | stick, which I can do myself too! If I search for 'hot air
         | rework' I get people trying to sell me kit. If an engineer
         | can't find a place for such repair in the largest megacity on
         | the continent, what hope is there for an average Joe?
         | 
         | Also for chromebooks and crapbook worth $200-$300, how is that
         | rare person going to charge for his time?
        
           | GrantZvolsky wrote:
           | Sorin[1] is based in some London repair shop. It is probably
           | viable because he repairs cheap laptops among other things.
           | He also takes mail orders, but I haven't seen him mention any
           | contact info in his videos.
           | 
           | [1]: https://www.youtube.com/watch?v=yBYpyI6OW64
        
           | varispeed wrote:
           | It's probably not viable as business. You can buy a rework
           | station for under PS100 these days and it does not take up a
           | lot space, so you could store it away in the storage among
           | other tools needed but rarely used. I mean, for instance, my
           | dad was never into electronics, but we had a soldering iron
           | at home, just in case a wire needs to be redone etc. Times
           | have changed and I see no reason why there shouldn't be a
           | rework station in every home. Maybe the name "rework station"
           | sounds misleading, like you would need a dedicated bedroom to
           | use it... But to redo a couple of chips is no different than
           | taking your blender from under the stairs to do a smoothie.
        
           | imtringued wrote:
           | I'm sorry but searching 'hot air rework bga' leads to better
           | results...
           | 
           | https://youtu.be/i9qC7x5QHIo?t=221
           | 
           | Don't forget that you must replace the solder balls on
           | desoldered chips with a stencil. Your new bga chip should
           | come with solder balls though.
        
           | sokoloff wrote:
           | Your last point explains your former difficulty. There's no
           | retail willingness to pay, but a lot of willingness to
           | inquire and waste someone's time. Start with an in-country
           | PCBA firm; they're likely to have someone or know someone.
           | 
           | Alternatively, inquire on an enthusiast forum (eevblog) or
           | talk to your local Ham radio club.
           | 
           | The same reason no one is advertising this skill to retail
           | buyers of $200 electronics is the reason to not include a
           | spurious $2-4 socket.
        
             | duskwuff wrote:
             | $2-4? If only. This socket is more like $50-60 -- probably
             | more expensive than the rest of the board.
             | 
             | https://www.aliexpress.com/item/1005001841972537.html
        
               | sokoloff wrote:
               | What would a (much more complicated) LGA 1200 socket cost
               | if it wasn't already a high-volume part? I can buy one
               | for $85 and they'll throw it in a retail box with a whole
               | motherboard, multiple PCIe, DRAM, DisplayPort/HDMI/VGA
               | connectors, Ethernet and USB controllers, as well.
        
           | Syonyk wrote:
           | > _Where do I find people who can do that?_
           | 
           | Your local hackerspace/makerspace is likely to have people
           | who can do it, though I don't know how you'd find people who
           | do it professionally. It's a bit of a weird niche, though as
           | the supply chains continue to crumble I expect it to become a
           | more popular one in the years to come. But if you can't find
           | anyone who does it, perhaps there's an opportunity for you to
           | jump into!
           | 
           | I expect this sort of thing to take the form of people who
           | buy "broken, parts only" equipment on eBay/Craigslist/etc and
           | fix it at their own location, on their own time, and then
           | resell it, though. It's less likely to be a customer facing
           | activity.
        
           | userbinator wrote:
           | Look for mobile phone repair shops.
        
           | dehrmann wrote:
           | > Also for chromebooks and crapbook worth $200-$300, how is
           | that rare person going to charge for his time?
           | 
           | I think you stumbled across the problem: troubleshooting and
           | repairing the device will probably cost $200. If the device
           | is under warranty, it's easier to send it back. If it's not,
           | it's more cost effective to replace it.
        
             | varispeed wrote:
             | It's not like you have to pay yourself $200 for repairing /
             | upgrading your device. But this is quite rewarding and
             | worth spending time on just for the feeling that you fixed
             | something. Certainly I would prefer this than spending an
             | hour watching Netflix.
        
       | imtringued wrote:
       | As others have said it would be more productive to just support
       | standard PC mainboard standards like DDR3 over SO-DIMM.
        
       | zerohp wrote:
       | Part of my job involves working with engineering sample SoCs on
       | development and characterization boards.
       | 
       | I've seen just about every kind of socket and connector you can
       | imagine but I've never seen a BGA socket that is reliable enough
       | to use in a normal machine.
       | 
       | They would never pass qualification use in a typical laptop.
        
       | metadat wrote:
       | The GDPR popup on this site is pure dark pattern, try saying "no
       | do not sell my data" and the next prompt auto-selects "yes sell
       | my data" with a default button of "Allow".
       | 
       | What Fucking Trash.
       | 
       | For anyone who desires reading TFA without the crap salad sando:
       | 
       | https://web.archive.org/web/20220421034027/https://www.cnx-s...
       | 
       | https://archive.ph/180ug
        
       | NovemberWhiskey wrote:
       | That's not an interposer; an interposer is a device that sits
       | between a device and a board and breaks out the interface so that
       | it can be probed with a logic analyzer or timing measurement
       | equipment or something.
       | 
       | This looks more like a test fixture socket - those things cost
       | more than the entire SBC does - so this seems more like a proof-
       | of-concept rather than anything practical right now.
        
         | wildzzz wrote:
         | An interposer doesn't have to have any breakout pads or pins.
         | It just needs to sit between a board and component. It can
         | serve as a breakout for components that may or may not be
         | compatible with the footprint on the board or may not break
         | anything out at all. I've used one to substitute a much cheaper
         | FPGA in for our very expensive one on the development
         | prototype. We didn't need all the features while sitting on a
         | test bench so we saved ourselves some money until a production
         | unit could be our dev platform. We had a few breakouts on the
         | board of some signals that were difficult to access elsewhere
         | but most just routed right through the interposer. We also
         | developed another interposer that replaced a bunch of deadbug
         | components to prevent rework from occuring due to poorly placed
         | deadbugs. There was enough money to get a little card made but
         | not enough to respin the whole board with the wishlist of other
         | changes we wanted to make.
        
       | eternityforest wrote:
       | Wow, that's awesome. This kind of thing could possibly make
       | Chromebooks and the like repairable.
        
         | Syonyk wrote:
         | What prevents you from repairing them now, exactly? Hot air
         | rework stations have come down dramatically in cost, and
         | there's no shortage of videos talking about how to do it. Try a
         | few scrap bits before working on something expensive...
         | 
         | It's nice to be able to swap things out with sockets, and
         | you'll generally find me coming down on the side of
         | repairability, but it exists with a variety of other
         | considerations, and something that is less repairable, but also
         | far less likely to fail in the first place, may be a better
         | option. Also, I rather like the fact that soldered on RAM makes
         | things like coldboot attacks a lot harder to pull off if you're
         | using trusted boot.
         | 
         | Heavy use of adhesives is certainly a problem, but I just can't
         | get that worked up over soldered on RAM.
        
           | Ekaros wrote:
           | When I think about it it could certainly make layman
           | repairing them cheaper. But I'm not sure if it really would
           | chance too much with professional work, the parts and labour
           | time would still be about the same or in same magnitude.
           | 
           | And how often does RAM fail anyway? Or if it needs to be
           | upgraded what about other parts?
        
           | ClumsyPilot wrote:
           | I don't have a garage to keep equipment that I will use once
           | in 3 years, I don't have scraps to resolder and that's
           | probably true for most people. For whatever reason a real
           | repairshop is a lot harder to find than a laundrette - I was
           | looking for one to fix a GPU, and I could not find one.
        
             | colejohnson66 wrote:
             | These sockets cost $60 _a piece_.[0] Four of them alone is
             | already ~$250. Add manufacturer markup, and you're looking
             | at an extra $300 to the consumer.
             | 
             | If manufacturers want to make RAM replaceable, they should
             | be putting SO-DIMM slots (which cost single digits),[1] not
             | BGA sockets. After all, the average consumer is more likely
             | to know how to procure RAM sticks than raw BGA RAM from
             | DigiKey, Mouser, etc.
             | 
             | [0]: https://www.aliexpress.com/item/1005001841972537.html
             | 
             | [1]: https://www.digikey.com/en/products/detail/10033854-05
             | 2FSLF/...
        
       | userbinator wrote:
       | This is... not really news? Yes, BGA sockets exist. Device
       | programmers and development/evaluation boards often have them.
       | Unfortunately they are not cheap, even direct-from-China:
       | 
       | https://siredatech.en.made-in-china.com/product/oSUJIjpOfwYD...
        
         | kurthr wrote:
         | I guess maybe they could be made at more reasonable pricing in
         | volume?
         | 
         | But you're right. I've needed to have small 100 BGA sockets
         | before and typical pricing of non-standard parts was $2k for 4
         | with a $1k setup fee.
        
       | [deleted]
        
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       (page generated 2022-04-24 23:01 UTC)