S-Series GA-EP45-DS5 GIGABYTE Motherboard problem

[Megalomaniac]

I just bought a GA-EP45-DS5 Motherboard and put it together in my computer, but when I got the computer starting the screen wont show anything meaning the graphic card is not connecting correctly to the PCI slot. I have a nVidia 8800 GTS graphic card, i tried putting in my nVidia 6600 and still the monitor would not work. I've done these things a quite a few times before (setting together a computer) but this problem just goes behond me. I have everything else connected correctly (as far as i know of) and the GPU just wont work! Yes I put the cable in from the PSU into the 8800 if u were wondering.

My computer specs:
Graphic Card: NVIDIA GeForce 8800 GTS
CPU: Intel(R) Core(TM)2 CPU 6400 @ 2.13GHz (2 CPUs)
RAM: 2GB DDR2
PSU: 450-550W (Not entirely sure, and I can only post when im at school so i cant check)
HDD: 1TB, SATA II
Monitor: 19" ACER AL1951 (Including this one since it wont display anything)

It might be the fact that I havn't dealt with a new Motherboard like this, so i might not have plugged something in that I should have, my old one was from 2005 and this one is very up-to-date. lol I feel old cause I've never seen so many SATA II and USB slots on one Motherboard, and I'm only 18

 

[jfenwick]

I have to ask but did you get the additional 8 pin power supply to the motherboard? Top left corner tucked in by the heat pipes behind the I/Os?

I frequently forget to plug that one in.

 

[Megalomaniac]

I have to ask but did you get the additional 8 pin power supply to the motherboard? Top left corner tucked in by the heat pipes behind the I/Os?

I frequently forget to plug that one in.

No, i did not but its too late for me to do that since I went back to the tech guys in the computer store and gave them the computer to let them figure it out.