Please update to the latest packages.. that error has occured to me when the mesa version was too old (=incompatible), and the amd64 version was not available for some time because of build-daemon problems. If you still can reproduce it with the latest packages, show what 'apt-cache policy libgl1-mesa-dri' outputs.
The reason why I marked it a dupe was that I got two confirmations on irc that the update fixed issues like this (KDE not starting at all, Compiz crashing the X). The update was not available on the archive, I just build it for them so they could test (32bit version, you seem to have 64bit)... ** Changed in: xserver-xorg-video-intel (Ubuntu) Status: Confirmed => Incomplete -- [i945GM] After loading background crashes back to GDM. Works with 'driver "vesa"'. https://bugs.launchpad.net/bugs/320821 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs