PC Automatically Restarts When Launching Game

[RickyAA1]

My newly built budget PC hates games... I am having a problem running any game at all, my PC automatically restarts every time I launch a game. I think it’s the GPU or maybe even the Motherboard or the CPU. All the parts in my PC are new except my CPU and Motherboard which I purchased off people on Gumtree. I am also borrowing my friend’s GTX 750 Ti GPU. When I remove the GPU and play games with intergrated graphics it doesn’t shut down but plays games with 15-25 FPS. Please help me!

Specs
Intel Core i5-3470 3.2 GHz (3.6GHz Turbo)
Gigabyte GA B75M D3H Motherboard
8GBs of DDR3 1333 RAM
Gainward GTX 750 Ti 2GB DDR5
Be Quiet! Pure Power 10 500watt PSU
120GB Kingston SSD
Cougar Panzer Duel Tempered Glass Case

 

[Cycloid Torus]

"PC automatically restarts every time I launch a game"
- turn off 'automatic restart on error' in BIOS if it is on

"GTX 750 Ti GPU"
- nice card - are you using WHQL driver version?...did you use DDU to fully remove older drivers?

"When I remove the GPU and play games with intergrated graphics it doesn’t shut down"
Which indicates system is fine, except...
- is card getting the right power? is there a 6-pin needed?
- inspect card slot... is there anything that has fallen in there?
- inspect card itself...brown spots?...dirty connector?
- install MSI Afterburner or similar and monitor stats on the card
- try another card