PC wont turn on. Suspect the heatsink

[studduckTH]

The other day I had just turned on my PC and got into the OS and it turned off. Then today I turned it on and as the OS was loading it turned off. Now it is alternating between switching on for a second and then turning off or not turning on at all.

Because of the differing timings I'm leaning towards the CPU overheating. I took off the heatsink and then reattached it but no luck.

I'm at a loss on how to continue troubleshooting it. Should I buy a new heatsink and give it a go? I can't get the PC on long enough to check the CPU temps.

Any help would be greatly appreciated.

 

[Nuwan Fernando]

If you remove the heatsink, Please replace the thermal paste before reattaching it. Clear the CMOS using jumper or batter removal. Once you get it working, go to BIOS/ UEFI and monitor for temps and voltages. Then you can get a better idea of what actually causes the problem.

 

[GrooperDude]

If you remove the heatsink, Please replace the thermal paste before reattaching it. Clear the CMOS using jumper or batter removal. Once you get it working, go to BIOS/ UEFI and monitor for temps and voltages. Then you can get a better idea of what actually causes the problem.

That's the way to do it