After upgrading from FC3 to FC4 having problems with X11: when leaving a session with Gnome Menue->logout, then the display hardware is not reset correctly: there remains a ugly pattern with red vertical stripes on my LCD display so nothing more is readable.
Additionally, switching from the X Desktop to consoles with Ctl+Alt+Fx shows the same colored console windows (not black ones).
Did somebody make similar experiences?
Are you using an nvidia card?