I just bought a working Motherboard with processor. I had to buy a new HDD and powersupply for it. Everytime I try to install windows 7 64bit it comes up with a c000021 fatal system error. I've reset teh bios to the default settings and have no idea how to fix this. Any ideas? The botherboard and everything else worked fine on my friends computer. The only thing different is the case, HDD and powersupply.