So about 6 months back I started getting random restarts and kernel power 41 critical events on a previously trouble-free 3 year old desktop I built myself. Ran memtest several times for many hours, no errors, same with GPU, CPU and hard drive tests, all clean. Eventually the problem killed my PC; it wouldn't turn on any more, it would just power up the fans and spin up the HDD, then crash, and repeat. No idea what caused it, ended up replacing the following parts:
The problem didn't go away.
Did the following:
Pulled out graphics card and used onboard graphics. Didn't help.
Reinstalled windows completely (on new SSD).
Plugged PSU into different power socket.
It went away for a long while (about 2-3 months), then started coming back about 3 weeks ago.
Bought a pure sine-wave UPS. Everything was fine for about a week and a half. Then just today it did it 4 times.
The only things that are left to replace are:
CPU cooler (CPU temps are fine, so highly doubt this is it)
This is the error log:
The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly.
"Plugged PSU into different power socket.
It went away for a long while (about 2-3 months), then started coming back about 3 weeks ago."
Well, what you did was plug the same psu in your pc to a different socket.
If you have another PSU handy with you, Replace your PSU in the pc with the one you have you have at hand.
Give it a shot. It might just work.
My PSU went bad twice and I thought it might be my Hard disc.