I have a 27" iMac with 3.06ghz processor 1tb hdd and 4gb of ram purchased around march and I am having a weird problem with the hard drive fan. I brought it to the genius bar and they said the problem was with a program i was running(I dont believe them). I find the problem to be strange. I keep my computer running all the time and restart from time to time but rarely shut down. I noticed that the fan was running at high rpm's and they only solution was to shut down and restart would do nothing to resolve the problem. Then I noticed up in the next week that the same problem was happening. I started noticing a trend it was happening at the same time every week on the same day. I look up if there is anything in Activity Monitor causing the problem and I find nothing. Currently the only apps I have running mostly are Google Chrome, Mail, Adium, Itunes, Echofon and Dropbox. I wouldn't think that any of these apps are causing this problem. Anyone have any idea what could be causing this problem? Any help will be appreciated.