/etc/sysconfig/desktop
The /etc/sysconfig/desktop file specifies the desktop for new users and the display manager to run when entering runlevel 5.
Correct values are:
DESKTOP=", where<value>""is one of the following:<value>"
GNOME- Selects the GNOME desktop environment.
KDE- Selects the KDE desktop environment.
DISPLAYMANAGER=", where<value>""is one of the following:<value>"GNOME- Selects the GNOME Display Manager.
KDE- Selects the KDE Display Manager.XDM- Selects the X Display Manager.
For more information, refer to The X Window System.