Computer Will Post but can't get in any OS MODE

[tzetsin]

I actually had this happen to me the other day, computer was doin something wierd, so after some half hearted trouble shooting i decided to reformat...
After popping in my windows disk, it worked fine, did the first reboot, few mins later it BSODs... then after that, i couldnt boot into the disk anymore. Was very weird because my computer was running just fine before i reformatted... I tried everything, Cmos resets, stripped the unit of all but essential hardware, swapped out the ram... nothing worked. Then on a whim i tried disableing all but one core in the bios, and strangly it started working fine... i havnt rebooted since to see if i could make it work again yet, i should do that today. running with one core sucks.