Grahics card crashes

[MatthewFisher]

The problem that i am having with this graphics card (EVGA gtx 560ti) is that when i load up any sort of game or do any stress test to the gpu the computer will shut down. i thought this could of been a temperature problem but the cpu runs at 60 - 70 degrees c under load and the graphics card runs at 50 - 60 degrees c under load. However to get this result on the gpu i had to downgrade the memory clock from 1053MHz to 527Mhz however i can keep the core clock the same at 900MHz. is there anyway to get the memory clock back at 1053MHz without the computer crashing so that the graphics card can run at optimal performance. i know that the graphics card has enough power as the specifaction asks for 500w. Any feedback would be great been trying to fix this problem for a while now.

 

My current system specs are:

Intel i7 2600 with stock cooler

EVGA gtx 560ti 1024MB

8gb ddr3 1333mhz ram

128GB samsung evo ssd

500gb Hard drive

gigabyte ga-h61m-s2p-b3 motherboard

500w psu

 

Graphics card specs