alt Hacker NewsThe user friendly option would be to print the amount of RAM in very large letters on the PCB. There happens to be a lot of suitable surface on the PCB to the right of the text "Raspberry Pi 5" on the PCB anyway (§). Right now the amount of RAM is hard to read and easy to modify (move a little tiny SMD resistor).
Drawback: You need different silkscreens for different amounts of RAM.
Btw, if you're worried about RAM-swapped units you can already verify them as described at https://geekworm.com/blogs/news/prevent-ram-swapped-raspberr...
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(§) as can be seen here https://pip-assets.raspberrypi.com/categories/1129-pcn/docum...
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No, this is not sufficient, since it would still allow you to swap to shite ram of the same size. This is an age-old problem for counterfeits. The ink on the chip/PCB isn't worth anything. The only way to actually catch this is to do a IQC that runs a full RAM test and hope that if you can't see a difference in performance (throughput, BER, timings, etc), then the chip is correct, with a bit of periodic de-lidding for anything suspicious/sampled. Then, if you can afford it, you blacklist the vendors that are caught changing things.
They also added a bit of internal ink, which is worth just a little more:
> we now also program in some other device attributes, meaning that switching parts of the same size may not work.
Working with vendors in China is entirely adversarial (mostly because their supply chain is vulnerable too), at this scale.
it can be very easily done by burning it with laser on prepared blank box on silkscreen - even iPhones are marked this way with their own serial numbers
the only reason why pis are not marked this way is because raspberry didn't wanted to (so far)
A little bit of acetone and a q-tip will remove the silkscreen, and then the PCB can easily re-marked by the scammer. Having a new silkscreen made is pocket change.