I was in the process of cleaning and upgrading my old p4 pc. I removed the processor and CPU cooler. I then cleaned the thermal paste and reapplied a new coating. I re attached the CPU Cooler. How when I switch on the pc it starts to boot up and then shuts down after a few mins. If I restart a beeping noise comes from the machine and it might flash up on screen that the PC shut down due to a thermal event. Any suggestions
More aboutintel heating
Go into the BIOS and see if there's any temps info. If so, watch it and see if it goes above reasonable expectations eg 80C etc.
Seeing as you just did it, you might want to redo the sink/paste. You might have used to much/little paste and its now causing issues. I'd also double check that you plugged the CPU fan into the CPU fan header.