They would need to open up the card to check. And I cant see why they would do that. As in the vast majority of cases, theyd find nothing, so have just wasted time in opening up a card.I would imagine it is pretty easy to tell if the thermal pads have been changed though? So when you send a broken card back they can just identify that and cancel the warranty.
Now rather than throwing the card in a test bench, checking if it works and moving on, they would need to employ more skilled staff at this stage which can take the card apart carefully. Inspect the pads and board, and then decide if they will honour the warranty.
At this point, it gets down to consumer rights too. If they told me "you changed the pads, warranty void", Id be throwing back at them to prove to me that my changing of the pads caused the card to fail.
If they continue to refuse, ill send a letter to the legal department that I plan to take them to small claims court.
At this point... I just cant see any of it is worth it. At BEST they save themselves whatever it costs to make a 3090. But now they might have to pay a lawyer.... thats more than the card is worth.
MAYBE your right, and they will prove my pad change is why my card failed. But I just cant see it... From what I have seen of nVidia RMA's, they are pretty quick turn around. And as said... for that to happen I cant see them wasting time opening every RMA'ed card they get.