Hi, i recently bought four new MB Pros (15inch, 2,4GHz, 200 GB HDD 5400). To my regret i diagnosed a silent but annoying noise coming from the left side of the keyboard. I suppose it is either the left fan or the HDD. I regulated the fan with FanControl, same noise. Now i am very convinced it is the HDD which causes that permanent noise. Did you make same experience? Has someone further information?