Example (don't use these settings obviously, but change them):
"pools" : [
{
"url" : "http://www.ulr.com:port",
"user" : "user",
"pass" : "pass"
}
],
"intensity" : "13, 17",
"gpu-engine" : "0-800, 0-850",
"gpu-thread" : "2, 2",
"scrypt" : true,
"api-listen" : true,
"shaders" : "800, 960",
"thread-concurrency" : "1600, 2400",
"lookup-gap" : "2, 2"
}
And start cgminer from that config: