before my computer crapped out on me, it would freeze and blue screen of death everytime i loaded up in XP, then I ran it in safe mode to install drivers which worked fine (thinking it was video card driver conflict). Then i went back to xp desktop and it bsod/froze again within seconds of start up.
Tried reformatting then went up stairs and bam broken. So it could be that even your second one is still faulty. If you read some of the reviews on newegg.com there have been people reporting 3 dead ones in a row. I don't know if its some kind of cheap manufacturing issue or what not.
But I'm definitely going to point my finger at the motherboard at this moment.