hey mistercoin,
I have a number of r9 290s mining x11, maybe these settings can get you started:
"api-allow" : "W:127.0.0.1",
"api-listen" : true,
"api-mcast-port" : "4028",
"api-port" : "4028",
"expiry" : "5",
"kernel-path" : "/usr/local/bin",
"log" : "1",
"queue" : "1",
"scan-time" : "7",
"shares" : "0",
"auto-fan" : true,
"gpu-threads" : "2,2",
"gpu-dyninterval" : "7",
"gpu-engine" : "1000,1000",
"gpu-fan" : "30-85,30-85",
"gpu-platform" : "0",
"gpu-memclock" : "1500,1500",
"gpu-memdiff" : "0,0",
"gpu-powertune" : "20,20",
"gpu-vddc" : "0.000,0.000",
"intensity" : "19,19",
"kernel" : "x11mod,x11mod",
"temp-target" : "70,70",
"temp-overheat" : "85,85",
"temp-cutoff" : "95,95",
"temp-hysteresis" : "3",
"worksize" : "128,128",
"lookup-gap" : "2,2",
"shaders" : "2560,2560",
"thread-concurrency" : "20481,20481",
"xintensity" : "0,0",
"rawintensity" : "0,0",
"failover-switch-delay" : "60",
"no-pool-disable" : true,
"tcp-keepalive" : "30"
}
Make a .conf and try using some of the values above. I think I get around 4.7 MHps per card with this setup. I'm using an older version of sgminer with 14.4 drivers and a few files from 14.6.
Try moving/removing your old *.bin files prior to running with an updated conf. This will generate a new set of files and hopefully they will work better.
... 
I will try these out and get back to you!
