A friend of mine has been having trouble with his computer crashing when he launches specific games. The two that I know of off the top of my head are Space Marine and Transformers: Fall of Cybertron. I initially thought that the problem would be his graphics card, but he swapped in a different one and the same games still crashed his computer. So I had him run a memtest, and that came back clean. Pretty sure it's not a temperature issue, as it's only specific games that cause the computer to shut down, and it happens instantly. LoL, WoW, SC2 all run fine. The issue also persists over a fresh Windows install (when he got his SSD), and that included all of the latest drivers. So I'm not sure what the issue is now.
AMD FX-4100 processor @ stock speeds
Sapphire AMD Radeon HD 6850
120gb OCZ Vertex 4
650W PSU (Pretty sure it's a Corsair)
Any ideas would be much appreciated. XD