[gdm-list] GDM crashes ubuntu 10.04

[dbclinton <dbclin gmail com>]

Hi,
I recently installed Edubuntu 10.04 (Gnome 2.30.0) and have experienced
half a dozen or so crashes (screen goes black, posts strange color
patterns and monitor loses signal - cycles this way indefinitely)
sometimes unassociated with any user activity at all.
The pre-crash logs all share references to GDM and, particularly, to a
file called custom.conf. Here's a typical example:

May  5 15:02:55 rishon gdm-simple-slave[1655]: WARNING: Unable to load
file '/etc/gdm/custom.conf': No such file or directory

In fact, there is no file custom.conf - but nor is there on a stable
Ubuntu 10.04 install on a different computer in the house. I borrowed
and renamed a gdm.conf-custom file from a working ubuntu 9.04 (Gnome
2.26.1) that I have installed on a laptop, but I don't know if that will
do the job.
Does anyone have any idea what's going wrong and how I can fix this?
Here are some log extracts:
=================
syslog:
May  9 00:46:53 rishon kernel: [11647.116012]
[drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung
May  9 00:46:53 rishon kernel: [11647.116029] render error detected,
EIR: 0x00000000
May  9 00:46:53 rishon kernel: [11647.117079] [drm:i915_do_wait_request]
*ERROR* i915_do_wait_request returns -5 (awaiting 532213 at 532208)
May  9 00:46:55 rishon kernel: [11649.480018] [drm:i915_gem_idle]
*ERROR* hardware wedged
May  9 00:47:06 rishon gdm-simple-slave[3627]: WARNING: Unable to load
file '/etc/gdm/custom.conf': No such file or directory
May  9 00:47:06 rishon pulseaudio[3624]: pid.c: Stale PID file,
overwriting.
May  9 00:47:07 rishon bonobo-activation-server (dbclinton-3623): could
not associate with desktop session: Failed to connect to
socket /tmp/dbus-gKShAWkQGC: Connection refused
May  9 00:47:08 rishon pulseaudio[3624]: main.c: Unable to contact
D-Bus: org.freedesktop.DBus.Error.NoServer: Failed to connect to
socket /tmp/dbus-gKShAWkQGC: Connection refused
May  9 00:47:08 rishon acpid: client connected from 3632[0:0]
May  9 00:47:08 rishon acpid: 1 client rule loaded
May  9 00:47:08 rishon pulseaudio[3641]: pid.c: Daemon already running.
May  9 00:47:10 rishon kernel: [11664.158445]
[drm:i915_gem_entervt_ioctl] *ERROR* Reenabling wedged hardware, good
luck
May  9 00:47:10 rishon kernel: [11664.492012]
[drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung
May  9 00:47:10 rishon kernel: [11664.492022] render error detected,
EIR: 0x00000000
May  9 00:47:10 rishon kernel: [11664.492916] [drm:i915_do_wait_request]
*ERROR* i915_do_wait_request returns -5 (awaiting 532215 at 532208)
May  9 00:47:12 rishon kernel: [11666.568015] [drm:i915_gem_idle]
*ERROR* hardware wedged
May  9 00:47:12 rishon gdm-simple-slave[3646]: WARNING: Unable to load
file '/etc/gdm/custom.conf': No such file or directory
May  9 00:47:12 rishon acpid: client 3632[0:0] has disconnected
====================
auth.log:
May  9 00:46:58 rishon gnome-keyring-daemon[1476]: dbus failure
unregistering from session: Connection is closed
May  9 00:46:59 rishon gnome-keyring-daemon[1476]: dbus failure
unregistering from session: Connection is closed
May  9 00:47:00 rishon polkitd(authority=local): Unregistered
Authentication Agent for session /org/freedesktop/ConsoleKit/Session2
(system bus name :1.33, object
path /org/gnome/PolicyKit1/AuthenticationAgent, locale en_US.utf8)
(disconnected from bus)
May  9 00:47:02 rishon gdm-session-worker[1370]: pam_unix(gdm:session):
session closed for user dbclinton
====================
messages log:
May  9 00:47:06 rishon pulseaudio[3624]: pid.c: Stale PID file,
overwriting.
May  9 00:47:07 rishon bonobo-activation-server (dbclinton-3623): could
not associate with desktop session: Failed to connect to
socket /tmp/dbus-gKShAWkQGC: Connection refused
May  9 00:47:08 rishon pulseaudio[3624]: main.c: Unable to contact
D-Bus: org.freedesktop.DBus.Error.NoServer: Failed to connect to
socket /tmp/dbus-gKShAWkQGC: Connection refused
May  9 00:52:32 rishon kernel: Kernel logging (proc) stopped.
===============

Thanks for your great work!