I'm posting to ask which graphics chip runs the external monitor on the 2012 Macbook Pro. The 2011 15-inch models force the discrete chip to run the external display, leading to a significant increase in heating and (this part is significant for situations with LCD projectors) a reduction in battery life. It would be a big plus for me if the 2012 models, Retina or not, use the Intel 4000 support and only resort to the discrete chip when it's actually necessary for stuff like Photoshop. Any observations on this so far?