I've had a 3090 FTW3 Ultra since release (Oct. 2020) and I haven't had any problems with it until today. I tried to play Control and the game would crash every 5-10 minutes. I wrote it off and tried to play Jedi Fallen Order a few days later and while it doesn't crash, I constantly get texture problems. Fog is black, pixelated squares appear, and the most annoying problem, sometimes fog becomes a disgusting yellow color and completely obscures everything. I tried googling for this issue and some people have had the exact same problem, and their solution was to underclock their card. I tried that but it didn't fix the problems. I've never played these games before on this card so I can't say whether they would have worked or not when I first got it.
 
Since it seemed to possibly be a VRAM issue, I tried running OCCT's VRAM test and sure enough I got 63k errors on every single pass. I tried a different program (GPUMemTest) just to be sure and quickly got errors there as well. This all points to faulty hardware but I haven't had any problems in Overwatch, Apex, or Elden Ring, and I tried in Fur Mark and didn't see any visible artifacting, so I don't know if the problems I had are only related to those games and if the tests I ran are somehow false positives. Do you think its worth opening an RMA? Is there something else I should try? I'd hate to pay the shipping and whatever else is involved just to find out nothing is wrong.