over clocking an acer s460?

so i have an acer s460 but the clock speed is onley 2.4 ghz full tilt id lov to get it up to 2.8ghz that wood be nice so if you have anny thereys how to pls tell me and i will try btw i have it in a difrent case and a kick ass gpu (ati radion 5770 @850mhz with the gigabit cooling thin on it