Hi. My PC randomly freezes and the only way to power it off is via the PSU switch. I did SFC scans and swapped out the old RAM with new one but it still freezes. I also scanned for viruses and ran CCleaner. I don't get any errors at all, it just freezes. I'm completely stumped, any help would be appreciated. Thanks. PC Specs: GPU: EVGA GTX 650 1GB CPU: Intel E5400 @ 2.7Ghz RAM: 2.50 GB Motherboard: ASROCK G31M-GS R2.0 PSU: ThermalTake TR2 600W HDD: WD 160 GB OS: Windows 8.1 Pro Nothing is overclocked.