okay so i downloaded smcfancontrol for my imac 20" 2.66 and i set up my cpu fan 1800 rpms for when i am ripping dvds but when i quit the app the fans stay at 1800 they dont go back to normal. When i set it back to default and i start ripping a dvd the rmps wont go up they stay at 1200 which is the default. I have even tried deleting the the app but the nothing changes. Am i doing something wrong?