I just built a computer with a ATI Radeon 5770 graphics card. It runs awesome, but the one problem I have is that I use a 46' Sony Bravia LCD TV as my monitor, but the display doesn't completely fill the TV screen. It is just slightly smaller but it is irritating. I have tried adjusting the resolution on the computer through the control panel as well as the Catalyst Control Center, I have made sure the aspect ratio on the TV is 16:9, and I can't think of anything else to do.
Additional Info: I have used my Dell XPS laptop with the TV as well and that fills the TV screen(NVidia 9600 Graphics).