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Does anyone has any experience with, for example mining Doge, with a R9 280X?
I would like to know if it is worth to mine with this card.
The R9 280X pulls around 850 kH/s of scrypt hashing on optimal settings without overclocking, and that's not half-bad. However, if you're serious about making an effort with this you should try locating an HD7990 instead. It costs just marginally more than the 290X but does around 1350 kH/s before overclocking, and can reach 1500 kH/s with a tiny amount of overclocking - assuming you can manage to cool it properly so it doesn't throttle down from the heat.
off topic, but what did you do to get 850 khs out of a 280x? I've got two (sapphire and a gigabyte) and under win 7 x64 i can only get 750Khps out of both ( total around 1500Khs. here's my config:
{
"api-allow" : "W:127.0.0.1,192.168.0.26",
"api-listen" : true,
"api-mcast-port" : "4028",
"api-network" : "true",
"api-port" : "4028",
"expiry" : "120",
"failover-only" : true,
"kernel-path" : "C:\\Program Files\\BFGMiner\\/share/bfgminer",
"log" : "5",
"no-submit-stale" : true,
"queue" : "3",
"scan-time" : "60",
"scrypt" : true,
"shares" : "0",
"auto-fan" : true,
"device" : "0-1",
"gpu-threads" : "2",
"gpu-dyninterval" : "7",
"gpu-engine" : "1070-1070,1070-1070,0-0",
"gpu-fan" : "0-85,0-85,0-85",
"gpu-platform" : "0",
"gpu-memclock" : "1500,1500,0",
"gpu-memdiff" : "0,0,0",
"gpu-powertune" : "-20,-20,0",
"gpu-vddc" : "0.000,0.000,0.000",
"intensity" : "13,13,13",
"temp-overheat" : "85,85,85",
"temp-hysteresis" : "3",
"vectors" : "1,1,1",
"worksize" : "256,256,256",
"lookup-gap" : "0,0,0",
"shaders" : "2048,2048,0",
"thread-concurrency" : "8191,8191,0",
"skip-security-checks" : "0",
"expiry-lp" : "3600",
"no-pool-disable" : true,
"no-show-processors" : true,
"no-show-procs" : true,
"no-unicode" : true,
"scan" : "opencl:auto"
}
I am getting 430Kh/s out of R9 270X's for me they were a win as thats all the store had....but 4 of them is paying off....