PC Turning Off and On at Random

[Vekkros]

My PC has been doing this for a while, but at random times, my PC will just shutoff and come back on, as if I flipped the back power switch off then on. It seems to happen most often while playing a game, then each time the system boots back up, becomes more common to the point where my PC is turning on and off nonstop, and I have to leave it turned off for a few hours. I'm not too sure when this first started, but I think that a recent lightning storm may have had something to do with it, as I had my PC plugged straight into the wall. I checked the temperature of my CPU and checked if it was being overloaded, and everything seemed normal, with my CPU at around 30c and under load, only using about 10% of its max power. A friend suggested that my PSU may not give enough watts, but according to PC part picker, my pc draws about 300 watts while my PSU supplies 550w. Here are my specs:

i5 6600k (default clock speed)
GTX 1060 3GB
16 GB Ram
1 TB HDD
120 GB SSD
550w PSU

 

[FabioXN7]

Ok, you said it happens most of time "while playing a game" sounds like something is overheating, thermal throttling or either PSU could not be providing enough power for your GPU, what about GPU temps ? 30c for CPU under load in games is really ok I would say, although never had seem such low temp while gaming. As for your PSU have you tried another one instead ? Maybe the lightning did some damage to it specially when you said your computer was directly puggled to the wall switch, I'm not saying that you shoud buy another one straight but try to find another PSU equivalent to do some testing just to be sure. Also BTW, whats your PSU brand?

 

[Vekkros]

Also BTW, whats your PSU brand?

Its an EVGA 550w G2 PSU. Strange thing is that I can play The Witcher 3 for hours on end and have no problem, then load up The Sims 3 and can't play for 30 minutes without it crashing.

 

[FabioXN7]

Its a good PSU btw, don't think it's the issue here, it only happens on the Sims 3?

 

[Vekkros]

Its a good PSU btw, don't think it's the issue here, it only happens on the Sims 3?

No, it happens in other games too, not just The Sims 3. For some games, I never get a single reboot, while in others, it reboots constantly. I've checked all the temperatures while my PC is under load, and everything is cooled off.

 

[FabioXN7]

Ok that could be a number of things.. I'll ask a few questions so we can figure it out whats going on -

1 - Have you checked your CPUs heatsink, if its entirely well placed? Sometimes even if the fan is working, but the heatsink is not well seated it could cause issues like these for sure.

2 - Have you tried running any stress tests on RAM, CPU and GPU? If you didn't try these

For cpu use prime95:
http://www.mersenne.org/download/

For GPU gputest:
http://www.geeks3d.com/gputest/

For RAM use MemTest86

http://www.memtest86.com/

While running these tests you might have a good idea of whats going on, if your computer shuts it down while running one of these tests you might probably find your answer..

3 - Have you tried running any Scannings or Cleaners on your computer? Try a Total computer virus scan and also run CCleaner for a pc cleanup in case anything is corrupted

4 - Have you tried switching the power cable to another switch on your house's wall?

5 - Have you tried cleaning your computer, RAM sticks or doing a Disk scan to see if there's anything wrong with it? If not try that as well, make sure all cables inside are well placed and in the correct inputs.

These are a few steps so we can make sure nothing is wrong with your hardware..

Try these and let me know how it goes..