Look at the back of the puter. You would see another place you can plug the monitor in if you have on board. Otherwise read further.
I would turn it off.
Pull the card out,
put it back in,
boot to safe mode,
if it does not see the new hardware and ask for drivers go to the next step.
Install the drivers from the disk, and reboot.
Then you hopefully have it running. If not I still think its using the onboad if its there.
This is the most simply way to do it without going into device manager. Then you would have to know what to look for so you dont screw up other drivers.