Getting between ~2300-2550 Mh/s with 290 and ~2600-3000 Mh/s with 290X (Elpida memory both) for mining DRK.
My parameters :
sgminer.exe -k darkcoin -o stratum+tcp://drk.coinmine.pl:6090 -u p.1 -p x -I 24,24 -g 2,2 -w 237,234 --lookup-gap 2,2 --gpu-powertune 50,50 --no-submit-stale --gpu-memclock 1450,1450 --gpu-engine 1100,1100 --thread-concurrency 27500,25000 --temp-target 91 --temp-overheat 93 --temp-cutoff 99 --auto-fan --gpu-fan 0-100
http://sensytive66.free.fr/sgminer_4.1.0_drk.pngGreat job for SPH Miner !