Windows 7: Computer turns off during games (hardware not faulty)

Hi, at first I thought this was a problem only when I had my monitor switched to 120hz because it turned off alot back when I had it on, so I had been playing with 60hz for a while and tried my luck turning it back to 120hz, worked for a few days but now it seems it cant handle it, even in 60hz. It's a newly built PC!
I have checked graphics card with Furmark and no problems there, ran memtest overnight, passed tests. I cant upload any minidump files because it is empty. I've reseating heatsink. I want to know what else I could do to find out what the problem is please!



Specs:
-EVGA GeForce GTX 560Ti DS Superclockerd 1024MB
-Intel(R) Core(TM) i7-2600K CPU @ 3.40GHz clocked @4.6ghz
-ASUSTeK Computer INC. P8P67 PRO REV 3.1
-8gb RAM DDR3
-750watt PSU

Could it be a problem with uncompatible overclocks? Had a few problems with the overclocking settings

If it was me I would set the bios back to default, play the game & see if it is stable or not.

Hi,

Since you have experienced overclocking issues before, I'd say this is the area to look at. Perhaps your PC is shutting down due to overheating?

I agree with Hipster that the best option is probably to reset your CMOS back to the default settings and see how stable the PC is whilst you play the game. Another alternative is to run a stress test on your CPU whilst very carefully monitoring your temperatures. This post will explain exactly what you need to do:

anyone mind taking a gander over my overclock settings?

Regards,
Golden

right, how would I go about reseting that, on the actual motherboard itself? or resetting it somehow in the bios, i tthink ive reset to defaults in bios so at least my cpu is back at 3.5ghz instead of 4.6

Also, find a program that will display both your CPU and GPU temps and watch them while you play (second monitor?) If the airflow around your machine feeds back on itself, your GPU temps can go insane after a half hour of gaming... I pipe all waste heat from my machine out of the room to prevent that very thing.

ALso double check the 12v amp rating of that PSU and for your card and make sure your not running it at it's max rating. 750 watts "should be" enough, but depending on the PSU, the 12V amp rating can be all over th map and possibly not enough for the beast of a GPU.

And yeah as others have said, overclocking while running games is insane stress on a system. A LOT of systems will crash at normal settings due to airflow or PSU problems as it is, add overclocking to the mix and it's almost guaranteed without very special attention to airflow and cooling inside the case.

You do that by loading the default settings in BIOS, which it sounds as if you have now done.

Now stress the CPU using the guide I referenced (not forgetting to monitor your temperarures closely using HWINFO64 - I cannot stress this enough!).

Make sure you know the TCase temperature of your CPU - check that on the Intel information page.

Regards,
Golden