With proprietary drivers, the first thing to try is to completely uninstall and purge them, then reinstall using jockey.
Next thing I'd try is to downgrade to the .33 nvidia driver; some folks have reported troubles with .40 that didn't exist with .33. Report back here once you've had time to do some further troubleshooting. ** Summary changed: - Xorg freeze + Xorg freeze - black screen after splash screen ** Package changed: xorg (Ubuntu) => nvidia-graphics-drivers (Ubuntu) ** Changed in: nvidia-graphics-drivers (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/987720 Title: Xorg freeze - black screen after splash screen To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/nvidia-graphics-drivers/+bug/987720/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp