How to fix p4 power connector making my pc go off?

[Mirca]

So I desperately need your help to fix my PC. Today i was playing video games and out of sudden my PC turned of, i checked inside and saw that cpu cooler was really hot (but I dont know if that was reason of PC turning off), so I cleaned dust from it because I expected that was the problem. But when I waited some time I tried to turn on PC but only fans turned on for some time and lights on front (green and red) turned on and then kind of started blinking, even green making pc make some small reboots I guess, few times and then even fans turn down totaly .
After unpluging various parts i found out that source of problem P4 power connector, but I dont know if it is motherboard or thing that brings power (is it called PSU).
If this info metters soething when I turn on pc before first small reboot there is moment when i get this screen which says press F2 to enter bios, but then there start small reboots without it.
I dont have big budget and not big amout of testing/ or extra parts to check if it is psu or motherboard. Please help thx

 

[clutchc]

Can you post a picture of the power connector as well as the header on the board so we can see what they look like? How did you determine the problem was the P4 connector?

 

[Mirca]

I am sorry but I cannot upload pictures atm. When everything else, but p4 is connected fans work without problems and green light on front works non stop and psu works ok, without noices. But when i connecrt p4 and turn it on again. Once in a 2-3 seconds psu stops working for a one moment forcing pc to restart and front lights ( green and red) to blink.
Btw I want to thank you for trying to help me.

 

[clutchc]

If you don't see anything obvious wrong physically with the connector or the header, I would suspect the PSU, the board, or the CPU in that order. If your CPU was getting extremely hot, something may have died on the board's voltage regulator circuit. Or the voltage regulator in the PSU may be over-volting.

The P4 connector feeds +12v to the portion of the m/b that regulates power to the CPU.