Hello, I hope someone can help me guide the troubleshooting of this problem, or recommend which parts to focus on. I am running my media center on my home built machine for about 2 years. It's an Intel 2.8ghz running on motherboard Intel865gbf. Heat synch is a Scythe Kamikaze. For the last week or so the machine has just shut off randomly (no BSOD/nothing). When rebooting the bios is reporting an overheat of the CPU which forced it to shut down. I've had intel active monitor running which is reporting temps around 36 C. No active monitor alerts are reported showing temp goes up to a certain threshold. This has happened after 10 minutes of running or 2 days. Same error message. I'm not sure if I should focus on the MB, CPU, or Heatsink (or any other piece of hardware). I've checked to make sure the heatsink is set properly, and it seems to be. I have not moved the machine at all. My next move is probably to remove the heatsink and clean the thermal grease, and then re-seet the Heatsink. Any other recommendations are appreciated. Thanks,

You do that, and while you are in there make sure you clean out the gunk accumulated over time on the CPU HSF and all other fans in the casing. The internet is a series of tubes!

I would clean out the system like Sabertooth says. I know 36C for a processor isn't hot at all. Some idle around 55C! check to see if the processor voltage regulators are getting hot. it's right beside the processors fan to cool it. Mine gets hot enouth that it will burn you if you hold your finger on them for five seconds. You also could try resetting you COMS by the jumper but you will have to reset your BIOS settings again.(should be in your Mother Board book) If you can't find it just turn your Power Supplie switch to off, unplug the cable and take the M/Bs battery out and put it back in. It looks like a big watch or laser pointer battery.