I installed the system-config-display and duly set up for a Viewsonic 21. This CRT has a 1993 date on it which likely predates VGA probing.

After setting the display size, root's gnome desktop failed to appear. So I got rid of the xorg.conf file, and the desktop came back on the next startx (or was it xinit?).

Strangely enough, the preferences-display now has a 1024x768 option, which is the default now.

During this messing around yum update repeatedly wedged on testing transaction. An ls also wedged. Both had to be killed with -9.

Another reboot and Linux felt much better. Yum update and ls no longer wedge themselves.

Mysterious.