Install NVIDIA driver Ubuntu
I have spend several hours to searching for find out "How to install NVIDIA driver on Ubuntu Operating System". So, for saving time of another people like me, I try to write short tutorial about it.
First you must determine version of your physical devide.
Choose suitable driver for your physical graphic devide: link
For example, my physical devide is NVIDIA Geforce 820M, I will install 'nvidia-390' version.
sudo add-apt-repository ppa:graphics-drivers
sudo apt-get update
sudo apt-get install nvidia-390
After you finish, restart your computer.
Good luck