Here is a work-around which fixed the issue for me:
1. In the stable version (in my case Ubuntu 14.04 AMD 64 kernel 3.13.0-44), open Additional Drivers then select the X.Org X server Nouveau display driver.
2. Allow the setup to complete. Reboot system. Confirm driver is working.
3. Reboot into troublesome kernel version (in my case 3.13.0-45). If Nouveau driver is working ok, open Additional Drivers then select Nvidia proprietary, tested. Allow that to install, takes a few minutes.
4. Reboot system. Nvidia driver should be working again. At least that works for me, although no guarantees on other versions....
5. Today I installed the update to kernel 3.13.0.46 and Nvidia driver is working fine again.
Here is a work-around which fixed the issue for me:
1. In the stable version (in my case Ubuntu 14.04 AMD 64 kernel 3.13.0-44), open Additional Drivers then select the X.Org X server Nouveau display driver.
2. Allow the setup to complete. Reboot system. Confirm driver is working.
3. Reboot into troublesome kernel version (in my case 3.13.0-45). If Nouveau driver is working ok, open Additional Drivers then select Nvidia proprietary, tested. Allow that to install, takes a few minutes.
4. Reboot system. Nvidia driver should be working again. At least that works for me, although no guarantees on other versions....
5. Today I installed the update to kernel 3.13.0.46 and Nvidia driver is working fine again.