Computer Random Shutdown

[FatelBlade]

My computer was custom built via ibuypower, and it used to run perfectly. I've kept it clean of virus's and the like, and I clean out the dust regularly. However, recently, the computer would randomly shut down. There would be no warning, it would just stop. I thought this was a problem with having two monitors, so I disabled one, but the problem persists. I don't know whats wrong with it.

Specs:
GPU: AMD Radeon HD 6770
MoBo: Gigabyte GA-970A-D3
PSU: Xion 700W
CPU: AMD Phenom II X6 1055T, ~2.8 GHz
RAM: Two 2G Sticks

I consider myself decent with computers, and I believe that it is an issue with the GPU overheating, or the PSU malfunctioning, however I am not sure if this is an issue with the components themselves or a software glitch. I have tried starting my computer in safe mode, but the problem persists.

 

[slomo4sho]

Have you checked the Windows Crash log or are you not able to get to that point without crashing? If the latter then I suggest checking your CPU fan or PSU as the GPU shouldn't overheat and crash under minimal load.

 

[FatelBlade]

I have went to the reliability log, and while it mostly consists of telling me Windows was not properly shut down, there is one instance of a video hardware error. This does not account for all of the other shut downs however.

 

[slomo4sho]

Do you see a blue screen before the crash? If not, then it is likely a faulty PSU.

 

[FatelBlade]

You are correct, there is no blue screen. The computer just shuts off without warning. If this is a PSU problem, would the only way to correct it be buying a new PSU?

 

[slomo4sho]

That would be the next course of action.

 

[Nuan]

Have you checked your CPU overheating issue? This happens due to CPU overheating too. Check the CPU if the heatsink dried or not.