Outputting video to a projector using a PCIe card

Hey guys. I recently bought a Blackmagic Intensity Pro card to use with Pro Tools, but was also wanting to route other videos (youtube, etc) out the HDMI port from my Mac Pro to a projector. I can't seem to find how to change the video outputs to route my desktop through the HDMI out on the Intesity Pro to the projector. It seems like this would be possible?? I could be wrong though. Any help would be appreciated!!

I'm using an early 2008 Mac Pro, OSX 10.8.2, and a Blackmagic Intensity Pro PCIe card.