Nvidia
From: http://www.binarytides.com/install-nvidia-drivers-ubuntu-14-04/Find out your graphics card model
Use the lspci command to find out the model of your graphics card$ lspci -vnn | grep -i VGA -A 12 01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GT218 [GeForce 210] [10de:0a65] (rev a2) (prog-if 00 [VGA controller]) Subsystem: ASUSTeK Computer Inc. Device [1043:8416] Here its GeForce 210
Find out the right driver version for your graphics card
Visit http://www.nvidia.com/Download/index.aspxFill in the details about your graphics card and system and then click Search. On the next page, it should tell you the correct driver version with a download link and additional information.
For the above GeForce? 210 card, it showed 331.67 as the correct driver which can be downloaded from the website. However we shall install the drivers from ppa to make things easier.