Hi, So me and my brother both have the same iMac, but we have one each. He walked into my room the other day and said that my iMac was making a louder noise than his [maybe sounds like a fan?]. Anyway, i barely have any applications on my iMac, i have 4 applications and about 500 songs, so it can't be anything to do with overflowing the mac. Can anyone tell me how i can make mine as quite as his, mine is not really loud it just makes a low buzzing noise like a fan. Thanks in advance.