If it's shutting down due to temperature (which can happen in 20 minutes or less, if the cooling fan is not working or the ductwork is clogged with dustbunnies), that would be in the BIOS, which is programmed into the motherboard's chipset, not in the OS. Honestly, the beancounters at Microsoft couldn't care less if you set your computer on fire and dance around it, as long as you've paid the licensing fees for Microsoft Bonfire XP first...
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Sodium is a metal that reacts explosively when exposed to water. Chlorine is a gas that'll kill you dead in moments. Together they make my fries taste good.