Use the 13.12 drivers and included runtime. Do NOT use the 14.1 drivers, or the APP SDK 2.9.
Use sgminer 4.1.0.
Run these commands first:
setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1
Use these settings:
sgminer.exe -o pool.url -u username -p password -I 13 -g 2 -w 256 --kernel zuikkis --thread-concurrency 8193 --lookup-gap 2 --gpu-powertune 20 --gpu-engine 1030 --gpu-memclock 1500 --gpu-fan 80 --scan-time 5 --expiry 10 --queue 0
Start there, and bump the engine up from 1030 to 1035, 1040, 1045, etc until your hashrate drops off, then go back down until it goes back up. That's your shweet shpot.