System blackout when playing games !!

[Tran_3]

Hi guys !!
So my issue is that when playing games (far cry primal, GTA 5, Mafia 3 ...) for like 20mins, my whole system suddenly blacks out and this has occurred 3 times. The screen is down, power down, ram down, everything is down. Then after 1 or 2 mins, the PC automatically restarts without pressing any buttons. All of the games are set max settings, FPS always above 100 (except for Mafia 3, only 70, sometimes down to approximately 60)

My specs:
Win 10 Pro-64 ( not active yet )
16GB Avexir DDr4 2400
Core i5 7600
GTX 1070 Colorful
Cooler master GXII 750W.
Mobo: ASUS B250m-k

Just bought the system a week ago, so pretty sure that no dust collected.
I have no watercooling system, just a Antec a4pro aircooling.

Some abnormalities I have found compared to what i've seen on the internet, which i think may cause the issue:
CPU temps and usage: always roughly 80 celsius degree and almost 99 percent usage.
Low-spec required games such as Sleeping dogs have no shutting down issue. Moreover, CPU temps and usage are pretty low.

Any suggestions would be helpful !!

Thanks you guys mo much !!!

 

[hang-the-9]

Could be a power supply issue, maybe heat although the CPU temps at 80 during gaming is not too bad.

Tr one RAM stick at a time, maybe test with another good quality power supply. Cooler Master is not the best power supply brand.