Displaying on a tv through a tv output

I am using the ATI 7500 and when I drag the display window to my tv it is black. I was wondering what is wrong with it. Is there a patch, update or option to check off. and of course When I hit full screen it goes to the primary monitor which is of course my monitor. how can I get it full screen or even to display on the tv at all. Thanks email andrewsmoore@hotmail.com