The fan may have died or become clogged. The HSF clamp may have come loose and the HSF is not tightly attached to the CPU.
I recently built a computer using:
Athlon 2800+
Ultra Socket A Fan (http://www.tigerdirect.ca/applications/SearchTools/item-details.asp?EdpNo=86205&CatId=99)
300 Watt Power suppy (Cam with case)
Ultra 512MB PC3200 DDR 400MHz Memory
XFX GeForce MX 4000 Video Card
Integrated Auio
Motherboard and any other information is avaliable if you require.
My proplem when I first put the system together was that the Windows XP installation CD would not format the drive. Brought the system back to tigerdirect where they changed the cpu and solved that problem. The computer worked well after that running normally. about 50 degrees idle. One day when I started it up I realised that the cpu temperature was up to 66 degrees idle. When windows loaded I noticed serious performance hits that made the computer unusable. I then restarted the computer and checked cpu temperature which I've seen at 73 idle at most. Now the computer does not boot. It turns on, displays a black screen for about 10 seconds and shuts itself off. I would appreciate it if anyone can help me troubleshoot this problem.

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