My PC randomly freezes (even in BIOS)

So i've searched the internet for quite a while and i've found tons of posts about this problem but none to have a solution for me. PC freezes randomly, sometimes even bios doesnt start.Also I have done:
Disk check
Reinstalling Win7
Memtest(ran for 5 hours no errors)

And no progress. Can somebody help me figure this one out ? My specs are
PSU:500W (Cant find more info)
GPU:GTX 660 (twin frozr)
Cpu:AMD Phenom(tm) II X4 840
RAM: 8GB Kingston Hyperx Blu
Motherboard: M5A78L-M
1 answer Last reply
More about randomly freezes bios
  1. did u made any changes to your hardware before the problem happens
    also try to check the PC after unplugging the VGA GTX 660 (twin frozr)
Ask a new question

Read More

BIOS Windows 7 Internet