No signal on monitor

[JWright33]

I've just built my first pc but I'm not getting any signal to my monitor. I've tried both dvi and hdmi. The fans, LEDs and the disk drive appear to be working. I've tried each of my 4gb sticks of RAM separately and attempted it without the gpu but still nothing

components:
cpu- intel core i5, 4670k
motherboard- asus z87-pro
gpu- gigabyte gtx 780
storage- 60gb kingston ssd / WD 1TB caviar blue
RAM- crucial ballistix elite 1866MHz 8gb (2x4)
power supply- corsair cx600m
monitor- asus VG248QE

ps, the computer won't turn off unless I hold down on the power button. Not sure if I should be worrying about this issue however it was turning off with a quick press at first

 

[JWright33]

UPDATE: I reset the CMOS, powered up the computer again (without the graphics card) and finally got a signal but when I add the graphics card it still says no signal. I'm assuming this means there's a problem with the graphics card and if so is there anyway to resolve it