Unknown problem, Possibly PSU

[Vertiginous]

One of the computers in my house has recently begun playing up and it will sometimes lock up and become unresponsive and the only solution is to reboot, We tried to determine the cause of the lockups and so far have had no success, We ran Prime95 and Memtest and ran a gpu bench mark and so far all of the components have held up, The computer has been formatted and the problem is still there, We suspect the PSU is at fault but we cant tell for sure, The psu is a OCZ ZS Series 750W '80 Plus Bronze' Power Supply

CPU: FX6100
GPU: 560 Ti

any ideas on what it could be?

 

[teppic]

It could be so many things, unfortunately. CPU, graphics card, motherboard chipset, etc. I'm assuming you've turned off any overclocks to rule that out?

Could you exchange the PSU with one of the others you've got in the house to test it?

 

[infyrana]

If you have multple pc's, try part swapping (unless you fear for any possible damage of course)

Do you have the capability to use onboard graphics ? An old school method of testing hardware is to run the base level hardware (bare minimum). So remove graphics, any other PCI cards, any and all hard drives / cd-rom drives etc. Boot into the motherboard bios if you like, or just at the prompt waiting for you to insert some sort of drive.

Leave this up and running and see if it hangs after some time etc. Add basic pieces of hardware to it until you find the hanging. If, for example, it's the GPU, run the machine from the mobo graphics and triple check it's all ok.

I am sure there are bundles of other ways to test, but that's a good starting point depending on how many devices you have that could be the issue, or if it's motherboard problems (in which case you're in for a tougher time, maybe at that point suggest a mobo bios reset to defaults etc).