Random lockups/screen freezing (no BSOD)

[pewpew_93]

Below are my specs,
120g sandisk SSD
i5-2500k (non OC atm) CPU
CMH 212 evo (cpu cooler)
G skill 8g DDr3 1600 RAM
Asrock z77 pro4 MOBO
Antec 520W high current PSU
670 gtx gigabyte windforce OC

I built this computer about a month ago and for the last few weeks I have been getting random screen freezes (no BSOD, screen just freezes, no mouse no nothing, have to reboot). This occurs during games as well as with nothing running. Tests I have done so far, run memtest and ram appears to be fine, run a hard drive check and that was all good. Have swapped out my PSU with a mates 650w and the error still persisted. Also took out GPU and error still occurred.
I also reinstalled windows 7 and I'm still getting freezes. Since I'm not getting a BSOD is it safe to say this is a software fault?

 

[nhasian]

to rule out the hardware you can boot off an Ubuntu or Fedora live CD and see if the problem persists.

 

[pewpew_93]

I forgot to add that I booted into safe mode and there was no freezing after 12 hours (computer will usually freeze from startup by 10 minutes to 4 hours). Is that the same as the two options above?

 

[dooglag]

Having the exact same problem :/ been looking for ages can't seem to put a finger on it.
Guess ill have to buy some new ram and see how it works.

If you find a solution please post it

Thanks