Nvidia Geforce 9800 GT compatible with Rampage II Extreme?

I'm having trouble with a built computer I have going on. I recently bought a Rampage II extreme with i7 processor, Nvidia Geforce 9800 GT and a power supply of 750w. I'm not into much of knowing the parts but I turn it on and my monitor and/or any other monitor doesn't turn on. I've ask everyone and their mothers and for some reason 4 days into this I still don't have solution. It does not beep as if there was a problem. I did connect everything correctly. I even took it to Tiger Direct but they want me to spend $120 for a diagnostic. Is my Video Card compatible with the Mother board? Am I missing something? Please Help, i'm turning desperate.