cgminer works just fine for BTC but LTC mining won't get temps over 50C
Here's the cgminer.conf for HD6770M I use:

"temp-cutoff" : "105",
"temp-target" : "65",
"intensity" : "13",
"vectors" : "1",
"worksize" : "256",
"kernel" : "scrypt",
"scrypt" : true,
"lookup-gap" : "2",
"thread-concurrency" : "3200",
"shaders" : "480",
"gpu-engine" : "815",
"gpu-fan" : "100",
"gpu-memclock" : "919",
"gpu-vddc" : "1.055",
"temp-overheat" : "100",
"gpu-threads" : "1",
"kernel-path" : "C:\\path\\where\\cgminer\\is" (double "\")


Hope that helps!