Hi, i have a p4 running windows xp, and just recently, the computer shut down while i was using it. Now, if i try to turn it on, the computer's hdd led goes on, but stays on(as if it were stuck or something), the fans run, nothing shows on the monitor, and it does not go anywhere. Also, i can't shut it down using the the power switch, i have to go to the back and shut off the power supply to turn it off. Any help would be greatly appreciated! please!