P8z77v-pro only boots while using IG graphics.

[Roodoe]

Hello everyone, it's been a long night. I recently received my P8z77v-pro motherboard today. I've had no problems booting the computer up and using windows with the IG graphics (vga). But as soon as I switch to my Radeon HD 7950 the motherboard's VGA light stays on, signalling that there's a problem with the vga of course. I've tried different graphics cards and none have worked.
I'm using a 750 watt power supply. Any help would be appreciated. Thank you.


I've tried:
Resetting the Cmos
Using an alternate card
Using different cables to connect to the graphics card (vga/hdmi)

 

[Roodoe]

Update: I used removed one of my cards from another system to use, and this time the red VGA light does not appear, but there is still no signal to the monitor. What the hell??? Could this be my power supply, or is it more likely a bad motherboard?

 

[Roodoe]

Update: Still no luck, i'm going to try getting a new psu from a local electronics store and returning it if that isn't the issue. If it's not, hello RMA.

 

[Roodoe]

Update/bump: Tried a new (1000 watt) power supply. Didn't work, still have the same issue. Can anyone help me?