My graphic card is a Mobility Radeon HD 4200 Series.
I tried these 2 answers from What is the correct way to install ATI Catalyst Video Drivers in 12.04 LTS?

But unfortunately, it does not work for me:

• When running the amd script, I get this error message:
  

  $ sudo sh ./amd-driver-installer-12-4-x86.x86_64.run
  ...
  DKMS part of installation failed.  Please refer to /usr/share/ati/fglrx-install.log for details
  

  

• When checking this log file, I get:

  Uninstalling any previously installed drivers.
  Creating symlink /var/lib/dkms/fglrx/8.961/source -> /usr/src/fglrx-8.961
  DKMS: add completed.
  Kernel preparation unnecessary for this kernel.  Skipping...
  Building module:
  cleaning build area....
  cd /var/lib/dkms/fglrx/8.961/build; sh make.sh --nohints --uname_r=3.2.0-24-generic-pae --norootcheck......(bad exit status: 1)
  [Error] Kernel Module : Failed to build fglrx-8.961 with DKMS
  [Error] Kernel Module : Removing fglrx-8.961 from DKMS
  Deleting module version: 8.961 completely from the DKMS tree.
  Done.
  [Reboot] Kernel Module : update-initramfs
  

• When checking with fglrxinfo, I get:

  $ fglrxinfo
  X Error of failed request:  BadRequest (invalid request code or no such operation)
  Major opcode of failed request:  138 (ATIFGLEXTENSION)
  Minor opcode of failed request:  66 ()
  Serial number of failed request:  13
  Current serial number in output stream:  13