Comment 1 for bug 820461

tested with Ubuntu natty
if I boot the live session and wait for gdm starts, the only graphical display I have is white and black horizontal static lines.

after a few seconds, the computer totally freezes.

As soon as GDM is started, I must quickly switch to the first terminal (ALT+F1) before the computer freezes, now, i've the time to work, the computer will not freeze anymore.

once here, i can create an xorg.conf file to properly restart gdm, here is the xorg.conf created file (from my remember, maybe I've made typo mistakes since I'm not near the computer anymore) :
##### --- /etc/X11/xorg.conf --- ####
Section "Device"
 Identifier "card"
 Driver "nouveau"
 Option "NoAccell"
EndSection

Section "Monitor"
 Identifier "monitor"
 Option "DPMS"
EndSection

Section "Screen"
 Identifier "screen"
 Device "card"
 Monitor "monitor"
 defaultDepth 24
 SubSection "Display"
  Depth 24
  Modes "1280x1024"
 EndSubsection
EndSection

Section "ServerLayout"
 Identifier "serverlayout"
 Screen "screen"
EndSection
##### --- END /etc/X11/xorg.conf --- ####

once this file is created, i can kill all "X" existing session by a kill -9 and make a start gdm
(don't know why the "stop gdm" command does not kill "X")

now, I've a functionnal live session and I can install ubuntu.