To fix the above error message use the following procedure
1) Download Newest Nvidia drivers from here
2) Open module blacklist as admin
gksudo gedit /etc/modprobe.d/blacklist.conf
Add these lines and save:
blacklist vga16fb
blacklist nouveau
blacklist rivafb
blacklist nvidiafb
blacklist rivatv
3) Uninstall any previously installed Nvidia drivers:
sudo apt-get --purge remove nvidia-*
4) Reboot your computer
5) When an error message pops up saying that Ubuntu cannot load Nvidia drivers, choose Exit to terminal (Exit to console)
6) Login and cd to the directory where you saved your file
7)Install drivers
sudo sh NVIDIA-Linux-x86_64-195.36.24-pkg2.run
8)Start GDM
sudo service gdm start