I have 8x r9 280x gygabyte and this settings

"failover-only" : true,
"scrypt-jane" : true,
"sj-nfmin" : "4",
"sj-nfmax" : "30",
"sj-time" : "1388361600",
"api-allow" : "127.0.0.1",
"api-listen" : true,
"auto-fan" : true,
"gpu-fan" : "0-100",
"auto-fan" : true,
"gpu-threads" : "2",
"gpu-dyninterval" :"7",
"gpu-engine" : "1000",
"gpu-memclock" : "1250",
"gpu-powertune" : "20",
"gpu-vddc" : "0.965",
"gpu-reorder" : true,
"vectors" : "1",
"shaders" : "2048",
"thread-concurrency" : "32768",
"worksize" : "128",
"intensity" : "12",
"lookup-gap" : "4",
"temp-target" : "75",
"temp-overheat" : "90",
"temp-cutoff" : "95",
"queue" : "0",
"scan-time" : "1",
"expiry" : "1",
"no-submit-stale" : true

My hashrate is 40kh 1xr9 280x
Can you help me get more hashrate please