On the cable box I've set it to 1080i, not stretched or anything, and is set to 16:9
The same kind of stuff is set on the TV, so they're in sync. Yet the TV has tons of artifacting and sometimes will randomly begin to flicker the video from black to whatever frame is being presented for seconds or up to a minute at a time.
This is not a new TV, we just found it while running around. It's a ln46c750r2fXZA (Pretty sure it doesn't have a proper name). Some video options are completely disabled / darkened out (Auto-Adjuct, Screen)