My friend comes to me with his hp pavillion 520c and says it wont work. He thought it was getting dusty inside and wanted to clean it. He took the heatsink off of the cpu, but touched nothing else. (such as ram or hard drives) He then blew the case out, and thought he replaced the heatsink properly. He booted the computer, it POSTed for about 6 seconds and then died, and he was never able to get it started again. He also started the PC with the case open, so he could see and feel inside. Immeadiatly after the computer died the first time, he said he felt the heatsink and it was "hot." He didnt say it burned him, so i cant be sure it overheated, maybe it was really warm, I dunno. There was no smell of anything burning to my knowledge.
When I turn it on, lights turn on, hard drives spin, fans get going, and the heatsink on the cpu eventually gets pretty warm after about 1 minute, but there is no signal going to my monitor. The video card is build onto the motherboard. My friend said he tried using a different card in one of the open slots, but he still got no display. I dont know if that has any thing to do with the orginial video card on board or not though.
ANd its not like I get some functionality, I get nothing. The cpu is an Athlon XP 1600+.