New Motherboard, Bad Graphics?

I bought a new PC with an ASRock B75M-DGS motherboard. I also bought two new Asus VH232H 23" monitors.

The problem i'm having is the graphics look horrible. Color banding, grainy, blurry/washed out video, fuzzy text. It looks like everything is in 16-bit color and some images have a posterization effect going on that makes them look like they're 256 colors.

At first I thought it was the Radeon 7850 that came with the system. I updated the drivers and tweaked the catalyst control center with no change. I then tried my old 7750 which is working great in my old computer, no change. I also tried the onboard Intel 4000 graphics, no change.

I also tried using just one display with DVI, then HDMI. No change.

Everything else in the new system seems to be working fine but the image quality is so awful that I started using my old PC again (with the new 7850 installed) and the displays are crystal clear.

Have any of you experienced this before? Could a motherboard cause the graphics to be terrible?

I contacted the manufacturer and they're going to ship me a new board but i've personally never come across this before.

I also tried re-installing Windows 8 and also installed Windows 7 but that didn't make a difference at all.

Thanks

Make sure you have everything plugged in correctly / all the way (4-pin power for the motherboard and anything for the graphics card). If your power supply is modular, make sure all the cables are plugged in all the way. I suppose it's possible that something is funky with the motherboard but if the new motherboard doesn't solve the problem, go through the entire computer and make sure there are no loose cables.