Hi, I have a 2011 MBP i5 13" which emits some noise when the displayport is connected to it to extend the desktop to a second display. At first I thought the noise was hard disk access, but after some experimentation realized it was not. The noise is correlated with video activity - if I move windows around the screen, play video, etc - it makes the noise. If I disconnect the displayport adapter, it does not make the noise at all. Also, if I set the system to only display on external display (turn off laptop screen), it seems to make less noise. I searched the web and forums and didn't see any reference to this - does anyone else notice this?