Good advice from Bigh4u2 in that hardware is the most likely culprit, and memory the most likely source of hardware problems other than oddball USB devices.
Overheating - I don’t think so. Modern CPUs/mainboards have overheating protection and will slow down and/or start beeping when they get too hot.
Unless it’s a Dell...
All kidding aside, I just recently had a processor quit working on a Dell I was servicing..
Although newer computers do guard against processor failure from heat, old ones don’t and many people, including myself, are running older P4’s which will die on you.
The Dell in question, and most Dells, don’t have anyway to monitor the voltage or temperature.
Granted that most of the time the reason for P4’s dying is because of a failing power supply. But not all the time.