I just built a new computer, it's an i7-930 with radeon 5870 in a micro ATX case. The computer started up and ran perfectly for the first day or so, including playing some games. However the first time I ran Crysis after like 20 min it suddenly shut down and resulted in a BSOD ("machine check exception). The way it shut down was it would exit to desktop and Windows 7 would start logging off and shutting down, not like a sudden power outage or something. The computer is able to restart with no problem, and runs normally until I play a game again. The only game I'm playing these days is Starcraft 2 and it happens during that too. I downloaded some temperature monitoring software, and it seems like the CPU temperature was at about 70-75 C when it happened. Also the last time it happened the game started stuttering and I would hear this noise, and then Windows would start shutting down like it did before. What's the likely problem here, and what should I do?