Hardware = 6770, 935 MHz OC (850 base) , 300 MHz UC (1200 base)
Miner = CGMiner 2.0.2, default settings, intensity=4 (process was tuned to use one core and priority was set to realtime)
To change the SDK's I used I put the opencl.dll file in the cgminer folder.
When the Mhashes current value in CGMiner stayed at the same value for 3 seconds or so I screenshoted it.
Windows Vista 64 bit, Catalyst 11.12, SDK 2.5
Windows 8 64 bit, Catalyst Consumer Preview RC10, default APP
Windows 8 64 bit, Catalyst Consumer Preview RC10, SDK 2.1
Windows 8 64 bit, Catalyst Consumer Preview RC10, SDK 2.4
Windows 8 64 bit, Catalyst Consumer Preview RC10, SDK 2.5