If you think it's because of heat, do something about that, like replacing the heat paste around the CPU and GPU, checking the vents and cleaning the inside of the case. Removing the side of the case and using a table ventilator to augment the air flow is a good test.
Sometimes there is some program or service in a loop, causing a 100% CPU usage. That's another explanation for heat. Then fixing that is a solution.
But maybe it's something else than heat. What does Windows' event log say?
My PC is getting restarted in less than 30 minutes. Its temperature is very high around 70 degree or more. So is it getting restarted because of that or something else might be problem.. Plz provide me with some solution

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