Crashing

[MVS801]

So about a week ago I had a problem with my pc freezing. I thought most likely a virus or just the fact that I had a ton of programs installed. So i reset and cleaned all my SSD drives, that fixed the problem. But now when I've been running high demand games my pc will occasionally just turn off as if I unplugged it from the wall, this doesn't happen all the time while gaming but its really annoying when it does while I'm playing Tarkov. it isn't even always while the pc is having to render graphics its happened once or twice while I was in my stash menu. my stats are ( Asus SabertoothFX990 R2.0, EVGA Supernova 1000g+, AMD FX9590, Sapphire RX580 8gb(main card), Sapphire RX580 Nitro+ 4gb(secondary card), 4x8gb HyperX fury DDR3 1866MHZ. its worth mentioning that it will always turn off eventually when I run Unigen Heaven. Also my gpu temp really never goes over 70c and my CPU rarely reaches over 60c. and yes I'm aware my ram isn't actually running at the 1866mhz its rated for, I'm not sure why but that's how its been since I built the system. 

[Kadzo]

This sounds like power problem under heavy loads but you have a sufficient PSU (even more then enough for that specs).

Do you have some spare PSU to test with?

Also what are the loads on the GPU when it crashes in unigen? 

[MVS801]

I don't have a spare but i could open up my psu and look for defects just not sure what id be looking for, blown or leaking caps maybe? and unigen uses both of my graphics cards while tarkov only runs one card(the 8gb)