Go to System Preferences > Display and there should be something that says Overscan, uncheck it. Also, check your TV's menu and try to tweak the resolution.
I clicked detect displays and get the same result. If I uncheck over scan I get a smaller box that is several inches smaller than the screen on all sides, and I can't find anything in the TV's menu to help. Any other suggestions? Thanks!
Alright, this will sound crazy, but this is how I managed to get it to work. I have overscan selected on my mac and "no overscan" selected on my TV. Strange, but it works! Thanks for your help guys!