PC restarts while playing graphically intensive games.

[Banapple69420]

Hey guys, I'm having a bit of an issue. Whenever I play graphically intensive games, like CoD: Black ops 3 or the Battlefield 1 Beta, my PC would randomly reboot itself. After a long time troubleshooting I found out that it was my motherboard that caused the issue because that was the only part that was not switched out, except for the CPU, and CPU stresstests, on stock speed and underclocked to 50% at a lower voltage, showed that was not the issue. Furmark on the other hand crashed my PC immediately with both the Sapphire R9 380 and the Asus GTX 470 videocards. I've also tested all the parts except the CPU on another motherboard, separately and together, but I was unable to replicate the problem.

Here is the weird part: I contacted the shop I bought the motherboard from to get it fixed, they declared it dead and sent me a new one. I know this is a new one because I forgot to screw off the CPU cooler bracket and I got one with the stock bracket. I got the cooler bracket back, though. So after reinstalling the motherboard and getting everything finished up, the problem still persisted. Any GPU benchmark and the above mentioned games crash my PC but it seems as though none of the parts are responsible.

Is there any way my CPU could cause the motherboard to overvolt or cause any other problem with the motherboard while preforming graphical tasks? Could there be anything else that might be the problem? Any suggestion helps!

System

Motherboard: Gigabyte 970A-UD3P
CPU: AMD 4300 @ 3.8Ghz
GPU: Sapphire R9 380 / Asus GTX 470 (not both, just tried them separately
PSU: Coolermaster B500

 

[burgessanthony]

PSU...poor quality unit. Don't use furmark on amd cards, completely unrealistic power draw.

New psu is step 1. R9 380 needs 28amps and that thing manages 24 max per rail.

 

[Chugalug_]

Almost definitely your PSU shutting down from OVP (overvoltage protection), it is poor quality anyway and will struggle under high load.
I would expect that system to draw about 550w most of the time under gaming load.
Get a new power supply, the R9 380 is a power sucker, as is your CPU.
Get this OP: http://pcpartpicker.com/product/R2mxFT/corsair-power-supply-cp9020103na

 

[Banapple69420]

Thanks a lot guys. I'll try out a new power supply and see if that fixes the issue!