I just set up my new 7970 for hashing, but can only push up the clock speed to 1150Mhz (of a maximum of 1500Mhz), before my drivers start crashing.
This is keeping my hash rate for this card down to 500-620Mh/s.
Also, at this speed, my fan is running at 84% and GPU temperature is a constant 76c
I am running it purely for hashing, while I use my 7850 for standard use, AND hashing.

I have 3 x 16x PCIe slots, but if I put both cards together, the 7970 heats up the 7850 terrifically so I've had to put the 7970 in the bottom slot.

Also, has anyone else found that the last version of catalyst dropped hash rates? I used to get 305 from my 7850, now, since updating my drivers, I only get 280.

Does anyone have any tips on how to get the best out of this set up? All help is appreciated.