Hi, only just seen your post.

Just to check quickly, as it wasn't in the command line you wrote - did you use -g 2 (-g is threads per GPU btw) with the 7970? If you don't put - g 2 in i believe it uses -g 1 which gives a lower hashrate.

I currently use this for my 7970's btw:       -s 2 --thread-concurrency 20992 -I 13 -w 256 -g 2    1040 gpu / 1500 memory (1081mV/1500mV)