This is not necessarily true. As seen with android devices you can force digital signature checking mechanisms by varying voltage levels in order to get the device to completely skip the checks as if they were never there.
https://research.nccgroup.com/2020/10/15/theres-a-hole-in-yo...
I'm sure a similar strategy could be developed here.
Slow down there. Glitching is almost never a practical long term strategy. It can take hours (or even days, depending on the target) to successfully bypass a check just once without other follow on effects. Glitching is useful if you need to bypass some mitigation once, such as to extract cryptographic keys, but it's not something you want to do every time you turn on your PC. Glitching gets substantially less reliable with every passing generation due to scaling (increased density/lower Vth increases the odds that you'll corrupt something else, particularly with EM fault injection) and design complexity (glitching out-of-order cores is a HUGE pain).
Of course, the only thing that'll POST are going to be just other vendor images from the same card model usually. (For different power limits, usually)
So, sure, you can skip the verification checks, but your GPU won’t be stable enough to be useful for anything
Also, as the chip and board here seems like an A100 reference design, using an A100 VBIOS image shouldn't fail any signature checks.
The lack of memory would be the most obvious difference. The A100 has 80GB, this has 8GB.
And I really suspect Nvidia probably some way of explicitly locking a chip to a given product ID, like efuses that the BIOS firmware can check on boot.
More sensible way to stopping that would be writing eeprom with encrypted key burned into the GPU itself but I doubt NVIDIA bothered, money loss for few people willing enough to take their GPU apart to replace a chip is insignificiant.