I am interested in getting an HD tuner for my PC because it seems NBC broadcasts HDTV over the air in the DC area. What I want to do is capture Late night with Conan O'Brien and Letterman too if possible. I'm probably right in thinking Conan isn't broadcast in HD so would the OTA NBC signal show it, or do they only broadcast HD shows in 720p/1080i resolutions? I'd love to capture this show in digitally transferred 480p instead of my crappy 480i Comcast analog signal (which is finnicky about certain channels, especially NBC). Thanks for any help!