How-To: Change Default Display Manager in Ubuntu 8.04

A display manager is a program that gives a graphical login screen and starts an X server session. Desktop environment KDE comes with Display manager kdm(KDM) and GNOME come with display manager gdm (GNOME).

Some time a user installs two or more desktop environments like kdm and gdm as display managers, and sometimes it's possible for the user to change default display manager . This can be done easily by using the command dpkg-reconfigure .

For example, if you installed KDE then GNOME, and the default display manager remained GDM, if you want change it use the following command : sudo dpkg-reconfigure kdm

The following commands can use for other display managers

dpkg-reconfigure gdm
dpkg-reconfigure xdm

If only one display manager is installed, the command will not respond.