Ubuntu supports the installation and uninstallation of proprietary ATI drivers.
Using the command-line, otherwise known as a “Terminal,” you can quickly uninstall ATI video drivers under Ubuntu. Ubuntu automatically activates a native driver for Linux-supported ATI graphics cards, but also supports installation of the proprietary “fglrx” driver. Some Ubuntu users need to install the fglrx driver to initiate certain features (such as 3D acceleration) of the graphics card. However, the proprietary drivers were not designed to work under Ubuntu, and may cause the operating system to freeze. In this case, the proprietary driver should be uninstalled.
Instructions “Accessories” > “Terminal.”
2. Enter the command “sudo apt-get remove xorg-driver-fglrx” and hit Enter.
3. Restart the computer and log in.
4. Navigate to the “System” menu located at the top left-hand corner of the screen, and select “Administration” > “Hardware Drivers.” The box next to the binary driver should be unchecked, indicating the proprietary driver was successfully uninstalled.