My computer has an ATI Radeon 4650 graphics card that is connected via HDMI to a 40-inch Sharp Aquos TV (model# LC-40E67U). When I boot off of the Fedora 15 install DVD my screen goes blank and my TV says it's not compatible with the video signal. My TV has a native resolution of 1920x1080 and it does properly report this to any hardware device that asks. Windows 7 works fine. What's wrong with Fedora 15?