I've recently built a new PC, it's my first build and I've managed to solve most problems that have occurred but I'm stuck on this one. It will load games fine if i load them straight from turning on the PC but if i run it for a while then load a game it resets itself, and doesn't leave and mini/memory dumps. The system runs fine normally and even with some old games but if i load a new game such as civilization 5 on steam or try running examples in UDK it resets.
Mobo: Asus Maximus IV Extreme
CPU: Intel Core i7 - 2600k
Ram: 8GB G.Skill RipjawsX
Graphics: Sapphire Radeon HD 7970 3GB
PSU: Antec High Current Pro HCP -750
SSD: Samsung 830 256GB
HD: Seagate Barracuda 2TB
Cooling: Antec Kuhler H20 920
OS: Windows 7 64bit Home Premium
At first i thought it was overheating but I've checked and the CPU and graphics card don't reach anywhere near a hot temperature before it crashes. I've also taken it to a local computer repair shop and the tests they ran all passed (i don't know what the tests they ran are but i'm going to call them tomorrow and find out / tell them it still crashes)
This is driving me mad so any help will be much appreciated,
Thanks in advance!