Here's my config for reliable 820 KHash

{
"pools" : [
],
"api-allow" : "W:127.0.0.1",
"api-listen" : true,
"api-mcast-port" : "4030",
"api-port" : "4030",
"expiry" : "15",
"failover-only" : true,
"kernel-path" : "/usr/local/bin",
"log" : "2",
"queue" : "1",
"scan-time" : "15",
"scrypt" : true,
"auto-fan" : true,
"device" : "0",
"gpu-threads" : "1",
"gpu-fan" : "50-75",
"gpu-engine" : "947",
"gpu-memclock" : "1250",
"gpu-platform" : "0",
"gpu-powertune" : "20",
"intensity" : "18",
"temp-target" : "80",
"temp-overheat" : "85",
"temp-cutoff" : "95",
"temp-hysteresis" : "1",
"worksize" : "256",
"lookup-gap" : "2",
"thread-concurrency" : "30592",
"no-pool-disable" : true,
"tcp-keepalive" : "30"
}