I gave that a shot but its saying 'no suitable device found' . Bummer.
Other tools show up the card just fine, they just dont let the ram clock go below 600. Still, its doing ~370/MH with that setting ATM.
Same, here. This is what I've found works thus far with my Sapphire 6950 unlocked to 6970.
1. Disable AMD Overdrive in CCC.
2. Use MSI Afterburner (after unlocking in cfg file) to set mV to 1.200
3. Use ATI Tray Tools to set Core 960 Mem 322 and Fan to 64%.
4. Use GPU-Z and set all Sensors display to Current Reading to ensure my settings are active and persisting.
For some reason ATI Tray Tools won't correctly set voltage, for me. With the above, I'm getting 400Mh/s consistently while currently hovering around 70C. I have headroom to experiment a little more, later. I'll just revel in having reached the 400Mh/s sweet spot for a while and monitor system stability.