I got an msi a88x g45 gaming motherboard. I have a new graphics card to but no drivers for it yet. I have my monitor plugged into the motherboard and my monitor is not displaying anything. I know it isn't the monitor I was just using it.
Plugging in a graphics card will, on some motherboards, override the on-board GPU automatically. Even without drivers you should get a low-resolution display from the graphics card. Have you tried booting with it connected to the monitor?