Comment 24 for bug 1401434

I may be experiencing a similar issue. Mine manifests on boot and also if I unplug my external monitor -- Xorg crashes and I am returned to a login screen.

I installed 340.76 to see if this would fix the issue, but it actually made it worse since now my laptop's built-in monitor can only run at 640x480 with that driver. Same goes for 352.21.

I got a notification during install of the drivers that a preinstall script failed or something to that effect, but continued anyway. The effect is the same, but there is no crash report generated with the updated drivers when I unplug my 2nd monitor.