I recently cleaned my mac from dust using an air compressor and the fan doesn't make as much noise anymore. It still does at times but it's not as bad as before. How else can I keep the noise down? I plan on bringing it to university next year but I don't want to be in class and my laptop is distracting and loud as crap. People have said to go to "Activity Monitor" but I'm not sure what to be looking for there..