How do I update the current video driver package used by Ubuntu 12.04?
Ubuntu's Update Manager automatically checks for upgrades to all installed packages on your system. However, the update schedule can differ from machine to machine.
To check for existing updates immediately, open Update Manager by either clicking the gear icon in the upper-right and selecting Updates Available ... or clicking the Unity symbol from the taskbar and typing "update manager'". Once Update Manager is running, do the following:
For more information related to video drivers, see https://wiki.ubuntu.com/Valve.