So I got myself an adapter and an articulating monitor arm for my late 2013 27" iMac the other day, and with the help of an app allows me to rotate my iMac 90º and use it in portrait mode. The screen looks even bigger vertically! There are lots of situations I would love to use it this way for. However, when I rotate it 90º the fan turns on full blast. Any ideas what this is about? Other than being noisy is there a danger of burning out my fan or wrecking something by running it in portrait mode?