Question PC restarting every 15-30 minutes

[HelpMe4444]

I bought a prebuilt 2 days ago, and I’m having issues with it restarting as in going black, power cycles immediately on and is back up in just a few seconds. It’s happening every 15-20 minutes, even if I’m just on discord or under load playing a game. I’ve already tried swapping my ram out, wasn’t the issue, I’ve done a full reset, re downloaded all my drivers, and windows, I’ve checked all my cables, I checked my psu for the 12v while running a game to see if it would fluctuate and it didn’t, 12.3v just about to whole time, monitored all temps, cpu nothing is breaking 55, and gpu isn’t even breaking 60. While gaming it said my cpu was using around 75 watts, gpu fluctuating between 160-205 watts. Even did a bios update, I can’t figure this out. The only thing I’ve seen when looking up is I did go to even log and there was a couple of kernel warnings and DECOM warnings but I don’t know if those would be causing the consistent restarts. Also have ran every benchmark I could think of to stress test it and nothing, it’s just around that time frame it does it.
Link to the specs

https://www.microcenter.com/product/645170/powerspec-g439-gaming-pc

 

[kurdtnz]

The one thing it doesn't list is the exact model PSU, unfortunately many prebuilds come with a cheaped out PSU. Can you see what make and model it is?

 

[HelpMe4444]

Microcenter is a few hour drive for me so I’m trying to avoid going back, I already spend 140 on more ram, and I didn’t want to have to spend another 160 on a psu, but if it fixes it I will

 

[HelpMe4444]

Model: MPE-7501-AFAAG

 

[RodroX]

That seems to be a Cooler Master MWE Gold 750 - V2, is that correct ?