I'm trying to configure Dual Monitors on a FC14 machine running Gnome. The machine has a new CPU and video card: HD 6450). Each monitor is a 1920x1080 LCD display. Currently they both work, but only in "mirrored" mode. I want to turn off the mirroring and extend the desktop to the second monitor. However, when I try to configure turn off the mirroring in Gnome's 'Monitor Preferences' tool, it complains that the maximum virtual screen size is 1920x1080.
I tried setting adding a Virtual screen to the xorg.conf file and then rebooting, but this didn't appear to have any effect:
Virtual 3840 1080
Does anyone know how I can configure Dual non-mirrored monitors each at 1920x1080?