Catalyst 13.9, Cgminer 3.7.2, Windows 7 64 bit

Model Name GV-R928XOC-3GD

Got it at 700kh/s with core clock @ 1020, mem clock @1500.

Rest of batch:

setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1
color 02
cgminer.exe --scrypt -o stratum+tcp://stratum5.dogehouse.org:3335 -u m -p x --no-submit-stale --thread-concurrency 16320 --intensity 13 --worksize 256 -g 2

Best I could get with my tinkering abilities. Voltage is locked unless I do a bios flash.

I've seen reports of people getting 740+ with the same card. My 7970's which I understand to be essentially the same card are putting out what they should at over 750 kh/s each (1085 core, 1500 mem clock). And I believe the 280x has the room for higher hash, temps are in mid 60's (celsius) at 700 kh/s.

Anyone have better luck? If so, did you have to flash bios, etc..?