My cudaminer for gigabyte gtx 760 cudaminer.exe -H 1 -i 0 -t 1 -C 2 -l K12x16 - got from 180kh/s to 280!! and then i havent even OC yet. This made my day!
HOLY WTF
my 660 with this setting use 100% CPU !
http://abload.de/img/unbenanntorfhu.pngWOOOOOOOW
which 660 are you using? My 680 is doing half lol. Though i have another rig i might build.