it goes to bios but crashes at the loading screen i tried booting in safe mode and it hangs at classpnp.sys.

my motherboard is a asrock g31m-gs r2.0
have done a memtest and no errors with the ram
have tried 2 different hard drives and both crash when loading windows.
have changed the CPU
updated bios, resetted bios.
tried to reinstall windows from cd that crashes also.
even ubuntu crashes from usb.

it can only be the motherboard, and i am hoping somebody had the problem and solved it.