Hi, All
I'm new to FC3. A friend installed it for me over the Memorial Day weekend. On several occasions over a 15-18 day time frame, when I came upstairs to work on it, I found the screen frozen. (Other times it was fine.) The only way I could get the system back was a reset or power down. Then one night after work I came home to find the screen waiting on input for the xorg.config program. Since I didn't know how to handle it (then) I quit out of it and did some Internet research.
Have you tried disabling the openGL screensavers? Just a guess, but in the past I remember having some problems with screen lockups with some openGL screensavers so I deselected them. Also had some issues with the screensaver power management of my monitor.
You didn't mention whether the screen lockups happened when you were logged in or logged out (with the login screen showing). I've had some different screen lockup issues with the login screen which I finally solved by adding a ServerFlags section to my xorg.conf file.
--Kenny
