Comment 17 for bug 1440012

I finally remedied the problem, using the xorg-edgers ppa. This is what I did -

1. sudo apt-add-repository ppa:xorg-edgers/ppa
2. sudo apt-get update
3. goto additional drivers and select driver 349.16
4. reboot
5. goto software/updates and goto the "Other Software" tab and UNCHECK the xorg-edgers ppa. I DID NOT PURGE THIS PPA.

The reason why I nixed this ppa is because after selecting driver 349, the software updater would try to pull in other updates from the xorg-edgers ppa which kept crashing my system. This allowed me to keep the driver 349 and not pull in any other updates. If you do a ppa-purge, it will also nix the driver, hence why i just unchecked it in the sources tab.