ATI video card in Debian GNU/Linux [Lenny] AMD64

Below you have the procedure that I followed to install my video card ATI Radeon HD 2600 Pro 512MB, using fglrx from non-free Debian repositories.  You shouldn't have any ATI driver installed, this is for a new Debian installation (that was my case).

First, as root:
    # aptitude update

Then, let's install the driver:
    # aptitude install module-assistant fglrx-driver fglrx-kernel-src

Now, make and install the fglrx module:
    # module-assistant auto-install fglrx-kernel-src

At this point, you must restart the computer to be sure the new module is loaded.   You will see the kdm or gdm won't change at all, it happens because xorg doesn't have the new configuration.  Change to one of the consoles ( e.g.: Ctrl+Atl+F1 ) and, as root, stop the display manager:

    # /etc/init.d/kdm stop
or
    # /etc/init.d/gdm stop

Next, configure xorg.conf with the new ATI card:
    # aticonfig --initial

Finally, restart the computer and you will see the change.  Log in with your regular user, open a term, and check the new configuration:

    $ fglrxinfo

And you will get something like this:
    display: :0.0  screen: 0
    OpenGL vendor string: ATI Technologies Inc.
    OpenGL renderer string: ATI Radeon HD 2600 Pro
    OpenGL version string: 2.1.7276 Release

For more information, check the Unofficial Wiki for the ATI Linux Driver out, where there are other ways using the proprietary ATI Linux driver.

Jose A. Viana