may be using the DEL key at boot time. Once in the BIOS, go to the temperature section and watch the temps for 5-10 minutes, see if it keeps climbing till it shuts off, or goes into unsafe area. If so, then replace the thermal paste between the heatsink and processor. Probably a good thing to do anyway since it's been awhile.
I can't post the specs ATM since its off but a year ago the PC i was using kept freezing/crashing(its from 2008/2009)Random times aswell, i could play for 5 hours with no problems or sometimes it'd happen after 10 minutes) and i haven't been able to use it since, i just did a fresh install of windows7 on the PC yesterday and now it barely even lasts 10 minutes, oh and it didn't freeze or anything while it was installing so idk. it was sitting idle for 6 minutes 37 seconds before freezing then needed to be shut down( yeah i know its bad but i had no choice otherwise it'd be on for nothing) I don't have money for a new one or replacement parts but what could be causing this? just old/outdated parts? The CPU usage reaches 100% even when i'd only have one thing open and it was CS:GO. No idea when thermal paste was last applied. The power supply was the only thing that got replaced.

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