Originally Posted by dfetzer 
I recently installed a ati 650 tv tuner in dell xps 420. The audio for ATSC comes through, but the video is just a green screen when viewing in Media Center. I unistalled/reinstalled drivers...any ideas?
Start up an ATSC stream (turn it to an ATSC channel), then minimize the Media Center interface (don't close, just minimize), and then check to see if you have any decoder programs running down in the lower ight hand corner (system tray) of the computer. If there is a decoder running there such as ffdshow, then you need to either uninstall ffdshow or change it so it doesn't attempt to decode your mpeg2 TV streams. If there isn't anything showing up, then it should be the normal Vista decoder running. That decoder should work fine for DVR-MS files from ATSC channels. Some things I could think of that may be causing problems: ffdshow video decoder (maybe), Nero media stuff (their bundled media software is obnoxious), other media software preinstalled on some systems (Muvee, iMedian, others). It is the only real thought I have at this point. Your video card should be fine, and the drivers for the 650 work for me in Vista. One thing you could of course try is to unistall the 650 software from add/remove prorgams and go get an older Vista 32-bit driver from ATI/AMD. That may be a solution. Also, if you changed drivers, you should run through the Media Center TV setup again just to make sure the registry gets set up correctly for the tuner to work. ...Out of ideas now. Good luck.
edit: could also just see if minimzing and then maximizing the media center interface makes it work. some have seen this kind of thing in the past. not likely, but it is an idea...