You Can’t Upgrade Soldered-On Laptop RAM? Think Again

Upgrading the memory in a computer is usually a straightforward case of swapping out a few DIMMs or SODIMMs, with the most complex task being to identify the correct type of memory from the many available. But sometimes a laptop manufacturer can be particularly annoying, and restrict upgradability by soldering the RAM chips directly to the board. Upgrading memory should then be impossible, but this reckons without the skills of [Greg Davill], who worked through the process on his Dell XPS13.

The write-up is a fascinating primer on how DRAM identification works, which for removable DIMMs is handled by an onboard FLASH chip containing the details of the chips on board. A soldered-on laptop has none of these, so instead it employs a series of resistors whose combination tells the BIOS what memory to expect. Some research revealed their configuration, at which point the correct chips were sourced. Surprisingly it’s not as easy as one might expect to buy small quantities of some RAM chips, but he was eventually able to find some via AliExpress. An aside is how he checked the chips he received for fakes, including the useful tip of hiring a dentist to take an x-ray.

The final step is the non-trivial task of reballing and reworking the new BGAs onto the board, before testing the laptop and finding the process to be a success. We’ll leave you with his final words though: “But next time I think I’ll just buy the 16GB variant upfront.“.

We’ve seen quite a lot of [Greg]’s work here at Hackaday, one of his most recent was this amazing LED D20.

59 thoughts on “You Can’t Upgrade Soldered-On Laptop RAM? Think Again

  1. > restrict upgradability by soldering the RAM chips directly to the board
    The data rates are getting so high that soldered on to the board provides the most reliable and is the cheapest option. The alternative would be to add a 204 pin gold contact SO-DIMM edge connector coated with a thick enough layer of gold plating to last at least the specified minimum 25 mating cycles. That probably adds 5 to 10 bucks to the BOM and it is a through hole part that needs to be hand soldered in place which will probably add another 1 to 2 bucks to the final price. The socket will also uses up a lot of area on the PCB compared to a BGA which adds to the end cost, and requires more traces on the board than a BGA would require. The gold contacts on the SO-DIMM plug needs be thick enough to also last at least the specified 25 mating cycles, and SO-DIMM modules have additional chips to deal with the problems from the edge connector so are not as cheap as a BGA which is additional an cost.

    DDR SDRAM modules ; LP-DDR SDRAM modules
    DDR5 288 pins desktop ; LP-DDR5 262 pins notebook
    DDR4 260 pins desktop ; LP-DDR4 260 pins notebook
    DDR3 240 pins desktop ; LP-DDR3 204 pins notebook
    DDR2 200 pins desktop ; LP-DDR2 200 pins notebook
    DDR1 184 pins desktop ; LP-DDR1 144 pins notebook

    For LP-DDR3 you are probably talking about a 96 ball TFBGA, which will be less traces on the PCB.

    A technically inclined person would pay a bit more and pick devices with replaceable batteries, and upgradable RAM and try and squeeze a few more years out of a product. But the bulk of people will just look at the price and pick the cheapest thing that meets their needs for now. They will bin it in 2-3 years (hopefully in e-waste) and buy something new that is shiny.

    1. Looking at the image above it is BGA has 178 balls which should be less traces required than the 204 for a DDR4 SO-DIMM. But the take away should be the same adding a socket adds cost.

      The sad truth is that most people are scared to open devices with a screwdriver let alone upgrade any parts.

    2. Thanks for this – I hadn’t realized the cost impact would be so severe. I put 2 weekend’s research into finding a laptop that could support up to 128GB RAM (found one, but what a nightmare).

      I tend to keep laptops for 6-8 years and a lot of folks were doing the same before soldered RAM.

      We must not forget that the present strategy generates far more e-waste than would otherwise be.

      Holding onto that notion, if we want to bend the waste curve downwards then there’s only two “other” choices: legislative carrots, or sticks (OK there’s a third choice: the status quo, pretending there is no choice… and/or getting angry at the messenger ).

        1. It definitely limits the scope for reuse though. While I fall into the enthusiast bracket I’ve picked up a few aged laptops, stuck in an SSD, upgraded the RAM and passed them on to non enthusiast users.

      1. What did you find that can be specced with 128 GB? My IT department managed to give me a Thinkpad with 64 GB eventually but it’s a Xeon processor, cost many pounds and weighs about the same as my car.

        1. It looks like there are some that are incrementally less chunky(eg. the Dell Precision 7560 is a bit lighter than Lenovo’s P17); but I doubt you’ll find anything notably cheaper or lighter; with the possible exception of a couple of ‘gamer’ models(cheaper, not actually lighter, the Asus G703GI-E5148T is 4.7Kg; but you may pay Nvidia less of a premium for a gamer-drivers GTX rather than a Quadro).

          Now that 4x SODIMMs allows for 128GB of RAM, 2x allows for 64GB, which really cuts into the audience for the 4x units; and means that it is almost entirely people who are looking for screaming power across the board.

      1. Sure let’s all buy a bunch of extra connectors we don’t need and have our laptops weigh more, perform worse, and have less rigidity, just to placate the people who don’t know how to plan ahead.

      1. Is this why this soldered ram is clocked at exactly same speeds as normal SODIMMs in other laptops?
        Even Apple with their M1 Package on Package ram doesnt clock it faster than ordinary dimm modules.

  2. I used to work at a place where we remanufactured off-road electronics (think of parts for million dollar tractors) and setting up to remove and re-install BGA chips was … a challenge. An expensive challenge at about $75K, and hiring someone from Kansas City onto staff to help iron out the process.

  3. I have been trying to figure out how to pull this off on my laptop (Lenovo) but I knew that the strapping resistors would be the problem and after a few weeks without my laptop and no schematics available, I ceded defeat and put it back together.

    I think it may be time to give it another go.

    Mostly, I am just ticked off that there isnt a simple sodimm slot in this thing. It would be added BOM cost, but there is definitely room for it. I even had to solder in my own M.2 socket to install an nvme drive because it was just… not installed on my model of laptop!

    1. Why don’t you just buy the right laptop in the first place? If you need to upgrade, why not sell the old one and buy a new one? If you are going to expend resources to upgrade, then really upgrade, get a faster CPU and the right drive from the get-go. Enjoy your nifty new machine.

      1. Yeah in a couple of years the sad is to small and MS decides to inflict windows 11 on you. And after retiring a high end laptop is not so affordable. Fortunately my laptop has the ability to add a memory dimm and replace the ssd which I have done twice

      2. Often laptops are only purchasable with a certain amount configurable, but have hardware support for amounts of RAM that aren’t actually available at the time. See: gaming laptops that came out around when a new RAM standard was introduced, ditto business laptops. DDR4 started out with 4-slot laptops only being purchasable with up to 64GB because 32GB sticks weren’t a thing.

      1. Yup. we’re supposed to throw away hardware and buy brand new. Upgradability gets in the way of a sexy industrial design. Even my PC laptop (ASUS ROG G15) did this in the weirdest possible way. It has half the memory on-board and half on an SO-DIMM. if you upgrade the memory it can’t run dual-channel and makes it slower. (*facepalm*)

        1. Why do you have to upgrade? Sell it to someone else and buy the right laptop. This is weird. Do you also expect to be able to upgrade your other appliances? Do you upgrade the motor in your dishwasher? Do you upgrade the compressor in your refrigerator?

          1. Does new dishes require upgrade of the dishwasher? Do ny refrigerator needs new and better compressor every few years to run? You clearly miss the point or just trolling

        2. tbh “X” seems to be on a mission of some kind. Like telling others what to do with their time, shoveling $$$ to corporations instead of servicing the stuff that still works for you and other fun stuff. I hope the dollars will always be with him!

          Seems like a genuinely good guy :D

          1. I don’t care what you think and I assume the reverse. You can take my advice or not, it’s up to you.

            Yeah I’m in favor of reducing consumption and recycling, selling your old laptop burns a lot less carbon than shipping a package of ram chips around the world. Better yet donate your old laptop to a low income student so they can share in your wealth.

            You should read the article again and pay particular attention to the very end.

    1. Laptop ram is totally different from dimm ram. Laptop ram is word sized because often there are only one or two chips. On dimms you have lots of chips so each chip is only one or two bits wide. Also laptop ram is unbuffered while dimms are buffered so you can plug in a bunch of them on the same bus.

  4. Do people out there live in an alternative universe where you can’t sell a used laptop? If you’re outgrown your computer I’m sure you can find someone out there who can make use of it as it is. Selling a used laptop is the best way to recycle it, with zero effort someone gets a “new” computer and you can get the one you really wanted in the first place. Hint: buy a laptop with good resale value.

    1. Dude, what is your agenda here? You have felt the need to reply to ever single comment with basically the same snarky comment about just selling a laptop and buying another. Have you seen the used laptop marketplace? You aren’t going to get much for a used laptop, so yeah, you might as well try to upgrade it yourself seeing as how THIS IS HACKADAY. Your advice would be great for Wired or Gizmodo or Tom’s, where kids have infinite money and buy a new laptop every month, but we like to push out limits and the limits of our hardware and try new things. It’s pretty much what we do here.

    1. A decade later, I took ram off a scrap motherboard and used it to replace 4x256kb ram on some SIMMs. Went fine, except the Mac Plus wouldn’t refresh it, so when it idled, it woukd crash when I moved the mouse. That’s when I read that ram couldn’t be properly refreshed in that Mac.

      I have a shoebox of RAM, when I started accumulating it, there was a future, at least for what I was doing. But now I’m not likely to bring home things that use SIMMs or ealy DIMMs.

  5. Can we please go back to the days of easily replaceable batteries, replaceable/upgradable RAM, and replaceable/upgradable storage? I don’t mind if it’s not super thin and sexy, I want something I can hold on to for some time and that can upgrade and repair as needed.

    I’ve been given laptops from other people that I managed to save from the trash and make usable by simply adding another stick of RAM and replacing the HDD with an SSD.

    1. @Tom Hargrave said: “Why did he have to reball the chips? Did he buy used RAM?”

      Yup, most likely DRAM that has been desoldered/salvaged from broken laptops or mobos, It’s even more common with CPUs. In the likes of China, India, and Pakistan E-waste is valuable, everything worth anything gets recycled. Slave labor is dirt cheap. I’ve heard of horror shops where kids pass PCBs through vats of hot used cooking oil, then the boards are hit with a stick and the unsoldered parts fall off into a basket, ball-less of course. After being washed and bagged the used parts are sold online. At some point in the chain the valuable parts are tested in a ZIF jig. The parts get reballed and soldered into “new” products. You can buy solder ball masks for less than a buck online. The solder balls are quite cheap as well. The masks and balls floating around online are there more for soldering old parts onto new boards, not so much for repairing old boards.

    1. You really think/believe Apple conformal coats anything? :—D They dont even do it to their watches.
      Neither is this laptop pcb covered in anything other than oxidation and dirt.

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