Random Reboots While playing games

[Kwstas]

Hello guys im having a problem for the last 2-3 weeks my pc reboots when im playing games

My Specs:
Cpu: AMD FX 8350
Ram: Vengeance 2x4gb CMZ4GX3M1A1600C9B
Motherboard: Gigabyte GA-970A-D3 (rev 1.4) Latest Bios
Graphics Card: EVGA GeForce GTX 970 FTW+ GAMING ACX 2.0+
SSD: Kingston SSDNow V300 120gb
HDD: Seagate 1tb if i remember correctly
PSU: Thermaltake Smart SE 630
CPU COOLER: Arctic Liquid Freezer 240

No its not and overheating problem I clean my computer every month.
I have tried prime95 on power consumption option computer does not shut's down tried using all the memory pc still ok tried using all of the cpu so it was going to overheat again never did shut down or reboot. I have also used FurMark to Stress my Graphics Card and it didn't shut down or reboot.
I have also tried disassembling my pc and re-assembled it the problem its yet to be fixed.The only thing that fixed the problem temporarily is changing the power cable of the PSU to a new one because when i applied this PSU to my computer i didnt change it with the new one.
By the way i also reinstalled win 10 just in case it was the problem, i will be waiting for your opinions.

 

[Zerk2012]

Run Prime 95 and furmark at the same time and when it does the same thing replace this with a quality power supply.
Thermaltake Smart SE 630

 

[Kwstas]

Run Prime 95 and furmark at the same time and when it does the same thing replace this with a quality power supply.
Thermaltake Smart SE 630

Tried it for about 15mins nothing happend used Furmark at 1920x1080 Fullscreen Anti-aliasing 8xMSAA and prime95 at power consumption option did not turn off or reboot do you have another ideas? or what might causing the reboots.