Hi, If your mac is over 6 months old, and the fans never kick on, download this program and kick the fans up to max rpm and let it sit for 15 minutes. After I did my mac ran cooler. As soon as I cranked up the fans a cloud of dust literally came flying out the back of my mac. It seems to aid performance when gaming if you kick up the fans even if your computer isn't running too hot. Heres the link http://www.macupdate.com/info.php/id/23049 Good Luck!