Shutting Down while playing game ?

Hello, I was experiencing PC shut down while playing games, so I changed PSU but the problem still on, Checked ‘whocrashed’ report and it says no dump file, so what might be the problem ?
Asus Sabertooth 990fx R2.0
Corsair Vengeance 4GB x 2 DDR3 AMD 8350 @4.0 GHz
Geforce GTX 650 1GB DDR3
Corsair VS 550 PSU Any help please ?
Answer #1
Check if your graphics card is running hot..
Answer #2
Have you tried monitoring the temperature of your PC? It might be an overheating issue. I suggest you clean your PC, remove all the dust that you can see.
Answer #3
do the normal stuff like virus scans and malware etc…. also you should check your fan for debris and make sure it is spinning correctly. also where do you have your machine? what changed that this started happening? retrace steps.