Below are the minimum RPM packages required that will also install all dependencies for Gnome Graphical display to be working on Cent OS 4.3:
# yum -y install xorg-X11 system-config-display gdm xterm gnome-desktop gnome-session
Run `system-config-display` to generate the "xorg.conf" file which will be saved to "/etc/X11/xorg.conf".
Set the runlevel to 5 in "/etc/inittab" and reboot.