used the config from suchpool
setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1
sgminer.exe --kernel darkcoin -o stratum+tcp://stratum1.suchpool.pw:3344 -u
USERNAME.WORKERNAME -p WORKERPASSWORD --thread-concurrency 8192 -I 13 --lookup-gap 2 --
worksize 256 -g 1 --gpu-engine 1160 --gpu-memclock 1450
http://suchpool.pw/docs/gettingstartedX11.pdf