No additional software is necessary.
Simply connect the video card to the 720p HDTV using the VGA cable or HDMI (if the TV has that port).
720p is a little odd. Older 720p HDTV will be recognized as 1280 x 720 or 1280 x 768 when connected to a PC. Newer 720p HDTV will most likely be recognized as 1366 x 768.
Many times when connecting a HDTV to a video card and you set the desktop to the HDTV's native resolution, the desktop will either be smaller than the screen (underscan) or the desktop is expanded beyond the screen (overscan). To fix the issue:
1. Launch Catalyst Control Center (CCC)
2. Expand the Digital Panel section
3. Click Scaling Options
4. Slide the control left / right until the desktop fits properly