Re: [ANN][Pool][Profit-Switch][Optional Auto-Exchange per Coin][Vardiff] ~ Hashcows
These shitty cards are amazing... With any other settings I get from my 7970 more than 540 KH/s (but no where near 700 KH/s), with your exact settings I get 413 KH/s. Fucking unbelievable... 
Been there, done that..... Until...... I found this thread :
https://forum.litecoin.net/index.php/topic,2963.0.html
I Flashed BIOS as described there and I'm now getting 750 Kh/s per 7970 instead of 450-500.
My bat file CGminer settings :
setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1
cgminer.exe -- scrypt -o -u -p --gpu-engine 1075 --gpu-memclock 1500 -I 13 -g 2 --thread-concurrency 8192 --worksize 256 --gpu-fan 80
Hope that helps.