sudo apt-get install fglrx

sudo apt-get install fglrx fglrx-amdcccle
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
  fglrx fglrx-amdcccle
0 upgraded, 2 newly installed, 0 to remove and 2 not upgraded.
Need to get 45.1 MB of archives.
After this operation, 129 MB of additional disk space will be used.
Get:1 http://gr.archive.ubuntu.com/ubuntu/ precise/restricted fglrx i386 2:8.960-0ubuntu1 [39.2 MB]
Get:2 http://gr.archive.ubuntu.com/ubuntu/ precise/restricted fglrx-amdcccle i386 2:8.960-0ubuntu1 [5,883 kB]
Fetched 45.1 MB in 3min 35s (209 kB/s)
Selecting previously unselected package fglrx.
(Reading database ... 128028 files and directories currently installed.)
Unpacking fglrx (from .../fglrx_2%3a8.960-0ubuntu1_i386.deb) ...
Selecting previously unselected package fglrx-amdcccle.
Unpacking fglrx-amdcccle (from .../fglrx-amdcccle_2%3a8.960-0ubuntu1_i386.deb) ...
Processing triggers for ureadahead ...
ureadahead will be reprofiled on next reboot
Setting up fglrx (2:8.960-0ubuntu1) ...
update-alternatives: using /usr/lib/fglrx/ld.so.conf to provide /etc/ld.so.conf.d/i386-linux-gnu_GL.conf (i386-linux-gnu_gl_conf) in auto mode.
update-alternatives: warning: skip creation of /etc/OpenCL/vendors/amdocl64.icd because associated file /usr/lib/fglrx/etc/OpenCL/vendors/amdocl64.icd (of link group i386-linux-gnu_gl_conf) doesn't exist.
update-alternatives: warning: skip creation of /usr/lib32/libaticalcl.so because associated file /usr/lib32/fglrx/libaticalcl.so (of link group i386-linux-gnu_gl_conf) doesn't exist.
update-alternatives: warning: skip creation of /usr/lib32/libaticalrt.so because associated file /usr/lib32/fglrx/libaticalrt.so (of link group i386-linux-gnu_gl_conf) doesn't exist.
update-alternatives: warning: forcing reinstallation of alternative /usr/lib/fglrx/ld.so.conf because link group i386-linux-gnu_gl_conf is broken.
update-alternatives: warning: skip creation of /etc/OpenCL/vendors/amdocl64.icd because associated file /usr/lib/fglrx/etc/OpenCL/vendors/amdocl64.icd (of link group i386-linux-gnu_gl_conf) doesn't exist.
update-alternatives: warning: skip creation of /usr/lib32/libaticalcl.so because associated file /usr/lib32/fglrx/libaticalcl.so (of link group i386-linux-gnu_gl_conf) doesn't exist.
update-alternatives: warning: skip creation of /usr/lib32/libaticalrt.so because associated file /usr/lib32/fglrx/libaticalrt.so (of link group i386-linux-gnu_gl_conf) doesn't exist.
update-alternatives: using /usr/lib/fglrx/alt_ld.so.conf to provide /etc/ld.so.conf.d/x86_64-linux-gnu_GL.conf (x86_64-linux-gnu_gl_conf) in auto mode.
update-initramfs: deferring update (trigger activated)
Loading new fglrx-8.960 DKMS files...
First Installation: checking all kernels...
Building only for 3.2.0-25-generic-pae
Building for architecture i686
Building initial module for 3.2.0-25-generic-pae
Done.

fglrx:
Running module version sanity check.
 - Original module
   - No original module exists within this kernel
 - Installation
   - Installing to /lib/modules/3.2.0-25-generic-pae/updates/dkms/

depmod..........

DKMS: install completed.
update-initramfs: deferring update (trigger activated)
Setting up fglrx-amdcccle (2:8.960-0ubuntu1) ...
Processing triggers for initramfs-tools ...
update-initramfs: Generating /boot/initrd.img-3.2.0-25-generic-pae
Processing triggers for libc-bin ...
ldconfig deferred processing now taking place