> RAM sticks have a little tag chip that tells a PC "how much RAM this stick has", but RAM chips themselves don't - so the device has to infer its RAM capacity from elsewhere
I'm surprised that in 2026 this is still true.
You could easily fit a little microcontroller on the die of each RAM chip which reports its make/model/manufacturing date, capacity and capabilities, can be triggered to run self-tests, etc. If they aren't doing that yet, I'm surprised that they aren't.
Why bother with the expense if you are permanently soldering it in anyway?
Well, it turns out they actually are bothering – while in DDR thru DDR4, the mode registers are write-only, LPDDR2 onwards have an MRR (Mode Register Read) command, which the CPU/chipset can use to inspect the manufacturer and capacity; and DDR5 has copied the same facility from LPDDR.
Upgrading my RAM firmware when
> or if someone finds a way to teach an off the shelf $1000 robot arm advanced autonomous microsoldering.
This sounds like an ideal application test case for precision industrial robotics, and I hafta wonder why we haven't seen an example posted here at HN.
The issue, of course, is just how much time, effort and skill is required to do it.
It might become a viable commercial process outside third world countries if RAM prices spike even more - or if someone finds a way to teach an off the shelf $1000 robot arm advanced autonomous microsoldering.
Then there's the problem of forcing the device itself to recognize the new RAM. It's a device-specific trick. RAM sticks have a little tag chip that tells a PC "how much RAM this stick has", but RAM chips themselves don't - so the device has to infer its RAM capacity from elsewhere. Like strap resistors on the board. Which you have to find and adjust for the new RAM capacity. That, or fix the RAM values in firmware, which is also device-specific.