With the open-source graphics driver stack found in the forthcoming release of Ubuntu 14.04 LTS (Mesa 10.1 + Linux 3.13), the performance of the community-developed Radeon Gallium3D driver is now close to that of the official AMD Catalyst driver for recent generations of Radeon graphics cards. In several OpenGL tests the RadeonSI driver can even run 80% the speed of AMD`s official Catalyst Linux driver."
Any major computer upgrade generally requires a full software reinstall too. No so if you heed the advice in the guide to Upgrading a Motherboard without Reinstalling. PCSTATS Tips