Works out of the box.
3D is disabled.
Install the "ATI/AMD Proprietary FGLRX Graphics Driver".
Source: ATI Radeon Linux Display
Download: ATI Driver Installer (ati-driver-installer-11-12-x86.x86_64.run)
Additional Source: AMD Support & Drivers
Default desktop GNOME3 and Cinnamon shows garbled menu captions. Some windows are warped.
Image care of Stereotypical:
See original post from here.
Choose MATE or the GNOME2 Classic desktop on the login screen. Don't use the GNOME3 desktop or the Cinnamon desktop (if installed).