I don't know if all computers do this but when mine hits 75C it shuts off. No beeps or forced restarts it just suddenly shuts completely off. It is something to look into though if you can figure out which value is which. I'm wondering if you get a pattern to the beeps. This is known as a beep code and it can very useful for diagnosing problems. Also do you get a back or blue screen? Do you get an error code? Have you tried running your computer in safe mode? Hit F8 repeatedly until you get a screen with advanced boot options. Have you tried a system restore point? Have you tried to scan your hard drive? In addition what is the make/model of your computer?

Also right click on my computer/computer --> manage --> Event Viewer --> Windows Logs --> System. Look for entries with an X. Please tell me what the most common entries are.

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