After an upgrade Ubuntu 5.04 to 5.10 my machine became unstable - GNOME started to crash at random, for no apparent reason.
I looked around for a while and the I found messages like the one below written to syslog by the gdm process:
gdm_slave_xioerror_handler: Fatal X error - Restarting :0
I tried using KDE instead of GNOME, but that didn't help.
I installed kdm and set it as a default display manager. That didn't help either, but the messages changed to:
X server for display :0 terminated unexpectedly
I did some reading and came to a conclusion that a display manager is not really necessary, so I uninstalled both gde and kde. It feels like an ugly hack to me and I don't a have a graphical login screen, but the system seems to be stable.