PC Shuts Down after game loading screen

CropperThe

Honorable
Dec 28, 2013
15
0
10,510
Hello,
-NVIDIA GeForce GTX 550 Ti
-Intel Core Quad 2 6600 @ 2.4 GHz
-4GB DDR2
-MB is Gigabyte EG41MF-US2H
-PSU 500W
-Windows 7 unoffic

About 14 days ago my PC started to shut down after I could see the first frame of the actual game after the loading screen (World of Warcraft and World of Tanks), this was happening 50% of the time. Then it got better for no known reason. I started playing WoW retail, but after around 1-2 hours of playing I started to have low fps, down to 1-10 max, then I had to restart the game and it usually got ok for another x hours or less then hour. I thought maybe the problem was the recent gpu driver I installed which was only beta. So I uninstalled, I actually found one that Blizzard itself recommends for this gpu and WoW, I installed that one and since then 95% of the time I start up WoW or Left4Dead 2 right after loading screen my PC shuts down (I usually can see the first frame of the game) and I'm not able to start PC again, unless I turn of my PSU for 10 seconds and then turn it on again. Gpu, cpu, MB temp is ok.

Thanks for any response.
 

CropperThe

Honorable
Dec 28, 2013
15
0
10,510
Maxpower PZ-500.I couldn't even find proper link on the internet. It's really average one. I already ordered new one, so I hope it will solve the problem. I will confirm it here after I get the new one. Thanks for your response :)