BSOD with GTX 275 in Crysis

Hello all, I built a new i7 rig about 3 weeks ago. Have been playing Crysis like crazy ever since. I had my first two BSOD experiences when I accidentally hit a button on my keyboard that is like alt-tabbing out of the game. When I clicked back into the game it immediatly BSOD'ed. I didn't think much of it as I played the game fine. Now I'm down to the end of the game and the damn thing BSOD's about every 15 minutes. I don't know what's changed, or what's going on. Doing some research on the internet I've found that many nvidia cards seem to be unstable playing Crysis. I'm not sure what to do about this problem. Any ideas? People say it's the drivers, but then I've found some things saying the GTX 275 OCX from BFG is just an unstable card in general.

Also, I've turned the fan up on my GTX275 because I don't like my card running at 85+. Is that going to void my warranty with BFG Tech? I'm going to be supremely pissed if I just wasted 250 bucks on this card. This is my first nvidia card because it sounded like they ruled the roost right now, but this may be my last as well.

Thanks for the response. I'm going to be calling them and trying to get an RMA. I'm just going to ask them straight up if I can just get a 285 and I'd even pay the difference. I've read too much now about the 275 OCX being unstable and I just wished I'd have found it before I bought it.