Have you flashed to the stilts bios? I'm getting about 715 khs out of the same card. It's usually in the 72-75 degree range.
I am a newbie to Mining. I do not know how to flash bios. Appreciate your suggestion.
I too get 740+ Kh/s when I set the GPU clock to 1030/ 1090 but the temp gets high upto 90.
http://rumorscity.com/2014/01/02/litecoin-mining-powercolor-radeon-r9-280x-sweet-spot-for-760khashsec/ But I am sticking to GPU clock 880.
As someone here suggested, I set the voltage to 1100 on MSI Afterburner and I am getting around 620 Kh/s & 78 C. I am afraid to push further for more Kh/s due to heat issues. If you are running the miner on windows, can you share your settings?
I'm running on windows with the following settings with sgminer 4.1 and usually run right around 715 khs.
"api-allow" : "W:127.0.0.1",
"api-listen" : true,
"api-mcast-port" : "4028",
"api-port" : "4028",
"expiry" : "120",
"hotplug" : "5",
"kernel-path" : "/usr/local/bin",
"kernel" : "zuikkis",
"log" : "5",
"queue" : "1",
"scan-time" : "30",
"scrypt" : true,
"shares" : "0",
"auto-fan" : true,
"gpu-threads" : "2",
"gpu-dyninterval" : "7",
"gpu-engine" : "1040",
"gpu-platform" : "0",
"gpu-memclock" : "1500",
"gpu-memdiff" : "0",
"gpu-powertune" : "0",
"gpu-vddc" : "0.000",
"xintensity" : "4",
"temp-target" : "75",
"temp-overheat" : "85",
"temp-cutoff" : "95",
"temp-hysteresis" : "3",
"vectors" : "2",
"worksize" : "256",
"lookup-gap" : "2",
"shaders" : "1792",
"thread-concurrency" : "8192",
"no-pool-disable" : true