The point about contacting your cable company is a good one.
The master RCA DLP thread at avsforum is at:
http://www.avsforum.com/avs-vb/showt...hreadid=264044
The thread is now 41 pages long and started about 18 months ago. I misremembered a little. Briefly: It displays 720p nativly if it receives it from the internal tuner. If the 720p comes in over the DVI it won't accept it. You need to send it 1080i over the DVI port (from your upconverting DVD/Cable/SaT Box) and it then converts it back down to 720p to display it. (Don't ask me ...)