setting for HD 7870's

setx GPU_USE_SYNC_OBJECTS 1
setx GPU_MAX_ALLOC_PERCENT 100
vertminer  -o stratum+tcp://POOL -u miner.worker -p pass --gpu-powertune 20 --gpu-engine 1150 --gpu-memclock 1210  -w 255 --lookup-gap 0 --thread-concurrency 6192 -g 1 --intensity 12

Im getting about 160khs, 72c

I Hope I can help some 7870's guy