dcrandall_7,
The resolution of the plasma usually ends in 768 instead of 720, and the 720 output may not work as a result of a resolution incompatibility. You can check your manual for acceptable resolution inputs. You might also want to see if that resolution is available on your game station either currently or after a console update.
--HDTech
I cannot get my TV to display on any higher resolution than 640 x 480 @ 60Hz with the VGA cable for my Xbox 360. If I go into the Xbox menu and change the output screen resolution the TV goes blank and says "mode not supported" The settings menu for the TV displays the screen resolution mentioned above with no apparent way of resetting it.

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