Playback computer for arena control room
 

I am in the process of designing a new control room for our arena. We are designing an HD ready room with a Utah Scinetific HD/SD-SDI router. I'm looking for an HD/SD-SDI card for a computer that I can use for playback of various video files, or maybe a Power Point Presentation or DVD. I thought the Black Magic Decklink Studio would do that, but it doesn't playback from QT, WMP or VLC just their software or an NLE. I could convert HDMI or DVI to SDI but I'm wondering if there is a card that will playback right out of SDI. Suggestions?