Hootla1 :
omensa :
You know, if the PC is restarting abruptly, without going to the BSOD. in my experience it only happens due to 2 things; Overheating or bad power.
Are you overclocking you CPU or RAM or GPU?
Before going towards a full Windows reinstall, I would recommend logging the temperatures of your CPU and GPU both, just to be sure that all temps are good.
If everything is in safe zone, open up your casing and change power cables with the spare ones if you have any in case your PSU is modular. If not, take it out and clean it thoroughly using a blower. Put it back and try gaming.
In most cases, this will solve the problem. Report back if it helps
I mentioned before, but to be more accurate the minimum my CPU goes to when idle is 30C, the maximum when gaming is 70C I believe the PC restarts (Cuts out) when it hits 70C as a safety pre-caution.
I'm not overclocking any of the above. I have already bought a new power cable and that did not fix it.
In a nutshell, if there is a software corruption, you get BSOD. If you have a hardware problem however, your system restarts abruptly.
If you are not getting BSOD that means you don't have any software issue. Meaning you don't need to reinstall Windows.
As far as I remember, the maximum temp for 860k is 70ish, maybe your system is restarting automatically to prevent any damage due overheating.
Just to be sure, download
AMD Overdrive and check the Thermal Margin during gaming. If its 5 or lower, than the restart is definitely due to heating.
You can disable the automatic restart in the BOIS of your motherboard, although it is not recommended as this will cause the processor to go beyond the safety limits which, in turn, may damage your system.
Other than this, try upgrading to an aftermarket liquid cooler like Corsair H80 etc and use good thermal paste between the cooler and the processor. This will help keeping the maximum temp in the range of 60-65 C under load and solve your problem.
Hope this has helped.