This looks to be a lightdm bug; X seems to have come up fine, then the greeter quits, lightdm asks the server to regenerate, then lightdm goes walkabout.
** Package changed: xorg (Ubuntu) => lightdm (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/819443 Title: X fails to start properly when using the open source radeon/ati driver To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/819443/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs