Computer crashing when playing games on high settings

Lysander92

Honorable
Aug 23, 2013
3
0
10,510
Hey guys, I hope I am posting in the right place and that someone can help me out.

I have a custom built PC with the following specs:

OS: Windows 7 Professional 64-bit SP1
Motherboard: MSI P67A-GD53
CPU: Intel Core i5 2500K @ 3.30GHz
Memory: Corsair 8.00GB Dual-Channel DDR3 @ 665MHz
GFX Card: 2048MB NVIDIA GeForce GTX 680 (EVGA)
Hard drive: 466GB Hitachi HDP725050GLA360 ATA Device (SATA)
PSU: Sweex dual fan 400W PSU (PS021V2)

I installed the graphics card above a few days ago, feeling that my old one was lagging behind the rest of my system. Since then, whenever I run games (specifically Borderlands 2 and Guild Wars 2) on high detail they run perfectly smoothly, but my whole computer shuts down with an immediate power cut if I play for more than 30 seconds without minimising the game. I get no error messages, and crash dumping software I have doesn't register the crashes. It is probably also worth noting that there is a threshold: if I play just below medium graphics without going to areas with heavy load, it won't crash.

I have all drivers up to date, and so I thought at first it was an overheating problem. However, after buying a new CPU cooler I have a max temp on each of my components of around 50 degrees celsius while the games are running, right up until I crash. I am now slightly at a loss as to what it might be as I am no PC expert, the only thought I had being that maybe my PSU is not powerful enough to run my graphics card (seeing as my old one didn't even need its own power input).

Thanks for reading, I hope you can help!

Rob