I got that when I had left over .bin files try deleting them, also you need only one of the --shaders or --thread-concurrency in there not both and the --thread-concurrency option should be a multiple of your shaders on the card less than the 8192 I have found to be the max that works for me so try 7168 for it from your example command used above. Also just noticed 5970s in your post they have 1600 shaders per core so 8000 is a good number to go with there, my script I use to start it with in a machine with a 5830 as first card in it, 5970 is second/third card.
cat ltc.sh
export GPU_USE_SYNC_OBJECTS=1
export GPU_MAX_ALLOC_PERCENT=100
export DISPLAY=:0
~/cgminer-ltc --scrypt --worksize 256,256,256 --thread-concurrency 6720,8000,8000 --vectors 4,4,4 --gpu-threads 2 -I 18,18,18 -g 1 --auto-fan --auto-gpu --temp-target 83
Memory speeds I have found to give me the max hashing rate for each model of card.
cat vset.sh
DISPLAY=:0 aticonfig --od-enable --adapter=all
DISPLAY=:0 aticonfig --od-setclocks=870,1170 --adapter=0
DISPLAY=:0 aticonfig --od-setclocks=750,1050 --adapter=1
DISPLAY=:0 aticonfig --od-setclocks=750,1050 --adapter=2
DISPLAY=:0 aticonfig --odgc --adapter=all