PC restarting while playing demanding games

[Predator_4]

Okay so the thing is thet my pc started restarting when i played the witcher 3 like 2 months ago , the other games were fine . But now when i play pubg , Rime or even Nier:Automata my pc just restarts , i checked if it was overheating but temperatures are normal. My specs are these:
Geforce gtx 960
i5 4590
psu of 800 W
8 gb of RAM
Gigabyte Model H81M-S2H (SOCKET 0)
i tried doing the DDU cleanup because it's not the CPU its like 59 - 60 playing pubg , but didn't work , please help.

 

[Tolis_GR]

Post your psu make and model. Most probably it starts giving up especially if it is not a quality brand

 

[Predator_4]

Post your psu make and model. Most probably it starts giving up especially if it is not a quality brand

The brand is diamond and model is LPZ26

 

[Tolis_GR]

Try another psu. I am putting my money that's the culprit

 

[Predator_4]

Try another psu. I am putting my money that's the culprit

Okay i'll keep you updated thanks.

 

[Predator_4]

Try another psu. I am putting my money that's the culprit

okay i've tried every game with my new psu , and its working perfectly thanks for the help.