Everything works fine until I run a player (Windows Media,RealPlayer,QuickTime etc). Then the computer will lock-up and I'll have to reboot. I know it isn't a hardware problem because when I use my previous hard drive, everything works ok! I think it's some kind of IRQ thing maybe ??? So far, I've uninstalled all of my players except QuickTime figuring that if I could get it to work, the rest would too. But even with the others removed, QuickTime still locks the computer when I try to play a file. My question is, what's the best way to trouble-shoot this type of problem since you cannot run QuickTime in Safe Mode??? Thanks in advance !