any thoughts on how to get 280x's stable with this gpu miner yet?
and why gigabyte 280x's seem to suffer very low hash rate, eg struggle to break 300h/s when compared to an asus 280x that does 360 with ease.
That's what you mean ? Gigabyte like my another rig ?

are they the windforce 280x's rev 1 or 2?
i run 2 of them and one can do 310H/s at 1200/1500 and the other does about 308H/s at 1200/1500. cant seem to push them any higher on mine. even tried different motherboards and the same affect, they are also the ones that drop out 98% of the time....
R9 280x Windforce Rev2. I do it with default clock 1100/1500. Stop OC your CoreClock cuz it will not stable and increase very little hashrate compare with power consumption. I suggest use default for best performance. If you want to OC, just increase a little with MemClock. FORGET TO OC CORE, IT'S NOT GOOD AT ALL.
mine also does not have Hynix GDDR, i have Elpida, which iam assumeing is a much poorer quality brand of memory. i will knock back the OC and list the results.
do you have stock bios, or modded bios btw?
and do yours stay at 99/100% usage or do they bounce around alittle?
Edit.
both cards running at stock clocks with only +20% to power, one does 292 and the other does 288h/s.
very low considering my asus 280x both combined do 730H/s :-/