Collect a full backtrace when reproducing this issue - see http://wiki.ubuntu.com/X/Backtracing for directions.
Also please attach the output of `lspci -vvnn`, and attach your /var/log/Xorg.0.log file. If you've made any customizations to your /etc/X11/xorg.conf please attach that as well.
Collect a full backtrace when reproducing this issue - see http:// wiki.ubuntu. com/X/Backtraci ng for directions.
Also please attach the output of `lspci -vvnn`, and attach your /var/log/Xorg.0.log file. If you've made any customizations to your /etc/X11/xorg.conf please attach that as well.