From the link that Zynfaith gave in her reply:
This AMD HD6950 should be the same drivers for all the HD 69xx GPU Cards: https://www.amd.com/en/support/graphics/amd-radeon-hd/amd-radeon-hd-6000-series/amd-radeon-hd-6950
Your AMD HD 6xxx are considered to be legacy GPU Cards and not supported by AMD Driver updates anymore. So you have two choices to try and see which ones works best:
WHQL 15.7.1 using the old Catalyst Driver or the BETA 16.2.1 using the new Crimson Driver.
