2011 MBP 13" Noisy when displayport connected

[chafey]

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?

 

[KwanMan]

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?

Takes more power to drive an external monitor => processor (integrated graphics) heats up => fans run faster => louder laptop

 

[chafey]

It doesn't sound like fan noise though - more like hard disk access (noise happens based on graphics activity - more graphics activity, more noise). No graphics activity - no noise.

 

[jonnysods]

I have two 24" ACD's and I can say that the comp makes a little more noise when connected to the ACD. As said above, it's more work for the comp so the fan speeds increase.