Open your terminal and address the abutting commands:
The abutting command it is for for install some dependencies and some packets bare to install accurately the driver.
$ sudo apt-get install module-assistant build-essential fakeroot dh-make debconf bzip2 wget
After that command you go download the driver ati
$ wget -c https://a248.e.akamai.net/f/674/9206/0/www2.ati.com/drivers/
linux/64bit/ati-driver-installer-8.42.3-x86.x86_64.run
Now you need run the installation
$ ./ati-driver-installer-8.42.3-x86.x86_64.run--extract
fglrx
Open the directory fglrx
$ cd fglrx/arch/x86_64/usr/X11R6
Probably you have a some files in this directory, such as...
$ ln -s lib64 lib
## One more link needed for 8.2
## begin 8.2
$ ln -sf libfglrx_gamma.so.1.0 lib/libfglrx_gamma.so.1
## end 8.2
#replace with lenny or sid when appropriete
$ cd - $ sudo ./packages/Debian/ati-packager.sh --buildpkg etch
$ cd ..
$ sudo dpkg -i fglrx-driver_8.42.3-1_amd64.deb
fglrx-driver-dev_8.42.3-1_amd64.deb fglrx-kernel-src_8.42.3-1_amd64.deb
fglrx-amdcccle_8.42.3-1_amd64.deb
OK, after input this commands, reboot your machine…
After reboot run this command:
$ fglrxinfo
And the result of this command should be similar to:
algoreal@dhcp-10-187:~$ fglrxinfo
display: :0.0 screen: 0
OpenGL vendor string: ATI Technologies Inc.
OpenGL renderer string: ATI MOBILITY RADEON X700
OpenGL version string: 2.1.7281 Release
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