Question GTX 750TI Black Screen Freeze

[AhmerWahid]

hi all, i have gtx 750ti gigabyte windforc black edition, when i play games it crashes constantly, i tried -500 core clock, -500 memory clock then i can play graphics demanding game for 10-20 min, and normal games like csgo i can play it for hours, gpu temp is below 70c, drivers are latest

 

[rgd1101]

full system spec? include make and model of the psu

 

[AhmerWahid]

full system spec? include make and model of the psu

Intel i7-3770
Foxconn H61MXV Motherboard
16GB DDR3 1600 Mhz Ram
Weed 500w Power Supply
Gigabyte GTX 750 TI Black Edition