Vista - Can't select Component Out only Composite

I just installed Vista64 bit for my home media center pc hooked up to my Mitubishi 52" DLP Projection TV 52525. Something is wrong with my VGA input on the TV (getting old, it wiggles), so I'm trying to use the component input to display 720p from my Nvidia 7800gt. Problem is I can only select Composite, or S-video output at 480i. I'm running component cables with the adapter that came with the video card. This wont display on my tv, no picture at all. However I do get a picture during boot. Bios, loading and welcome screen all show up perfect. As soon as desktop loads up, screen blinks and dissapears for good. Only way I can view my desktop is using Logmein.com.

Anyone have a solution that doesn't require any more purchased items? Registry tweaks? SOMETHING?

I do have a friend willing to sell me an ATI 4850 as soon as he buys a 5870 sometime in the future. Can't wait for this.