Specs
E6420
7900GTX
40Gb IDE drive
DVD RW IDE
Foxconn 945G 7MD
2GB DDR2 PC5400
400watt generic PSU
old 19" CRT monitor (HP 92?)
Problem
When using the computer there is a slight freeze up every 20 seconds or so which is most noticable in games. Initially he thought he had cracked it when switching to his backup hard drive and removing an old problematic one but there still seems to be problems. Graphics card & mouse have been replaced and therefore ruled out. Various diff motherboard drivers has been tried and the bios has been updated to the latest one.
I had a feeling it could be the PSU with it being generic. Another thing which suggests this to me is that when he has a lot of usb devices plugged in he sometimes cant boot up the computer. It could also be the motherboard is dodgy though so he doesnt want to go and buy a new PSU when its actually the mobo as budget is tight. He has no way of substituting the PSU or the motherboard to check them unfortuately. Another suggestion he has been givin is it could be the monitor not refreshing properly, but again he has no spares.
Anyone any ideas?
Edit: On COD2 when the FPS is limited to 125 it lags more than at 250.