No Video output

Okay so here is the thing, i built my computer a little while ago and it has been having an issue, Sometimes all the lights turn on and the fans spin up but there is no video output and the power button doesn't work.

Weird part is usually if i wait (or reajust the GPU in its slot) it turns back on, any idea about what is going on??? (i am positive the motherboard is not getting grounded and the wiring is correct)

(i have a GTX 780 graphics card, 16 gigs of ram (2 sticks), 1tb hard drive solid state, AMD FX-8350 cpu, GIGabyte GA-990FXA motherboard)