A system I've been working on keeps getting the nvlddmkm.sys driver failure over and over while under moderate stress (ie in a game) and continues to fail and recover until it inevitably BSODs. I doubt it's a power issue as the system has a rock-solid corsair 750w PSU running 2 9800 GTs and some flavor of quad core (maybe Q6600, I can't remember). The ram is corsair xms2 and although I haven't tested it yet I've seen no evidence that makes me suspect that it's the problem. What's strange is that the machine will BSOD when both 9800s are in, whether or not they are in SLI. With one of the cards in the system seems stable, but when I run it with the other it starts the cycle of BSODing. Identical cards with identical drivers. What gives? Is one of the cards perhaps bad? If not, why would one screw up and not the other? Thanks for the help.