ns____ :
hi sir im tottaly upset gpu not working i dont know y
Lol you bought that really fast.
As I fixed my post earlier I overlooked two things:
1) The XFX XT 600w, even though It's a large wattage PSU, only has 24 Amps on the +12V Rails and comes with only a 6 + 6+2 PCIe connector.
2) That particular GTX 980 Ti model requires 8+8, for the 980 Ti, that's pretty rare.
Either upgrade the power supply to a decent 600-650 watts model, or return the GTX 980 Ti and go for the GTX 1060.