#6 Install Restricted Drivers (Graphics Drivers, Webcam Drivers and Wireless Drivers) in Ubuntu 12.04
For Graphics/Video card
If you are using any graphics/video card or sound card or webcam then you must install the appropriate drivers/softwares for that. Ubuntu 12.04 can automatically detect graphics card and a pop-up window may appear with the suggestion but you need to make sure that you’re installing the right driver for the device. In the snapshot (below) – you can see I need to install Nvidia proprietary drivers in order to enjoy the power of graphics card.
Install Nvidia Driver in Ubuntu 12.04
Sometimes even it won’t be detected automatically, in that case you can install manually (go to System Settings -> Additional Drivers). You need to do the same thing for sound card, otherwise you may be facing some sort of performance problem or instability.
Open your Terminal – Ctrl+Alt+T, and paste these commands
sudo apt-add-repository ppa:ubuntu-x-swat/x-updates
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install nvidia-current
sudo apt-get install nvidia-settings
Install ATI Catalyst Drivers in Ubuntu 12.04
If you have a ATi video card or built in ATi graphics chip you can go for ATi Driver.
sudo apt-get —purge remove fglrx* sudo apt-get install dh-make execstack dh-modaliases dkgcc1 libc6-i386ms lib32
this will install additional packages to install ati driver then
Go to amd.com and download your driver
sudo chmod +x ati-driver-installer-11-10-x86.x86_64.run
sudo sh ati-driver-installer-11-10-x86.x86_64.run —buildpkg Ubuntu/precise
this will build the packages from the scratch and install the ati driver
Source : sudobits.com, smashingweb.ge6.org