Hi, TL;DR How loud is the 15" MacBook Pro with discrete 750M GPU when in clamshell mode driving an external monitor and running light/moderate tasks (web browsing, iTunes, YouTube, text editing, terminal, etc). Long version: I've got a base 15" Retina which is probably going back due to the yellow tint problem. I waffled back and forth on whether to get the base or the upgraded version. What I really want is 512GB SSD and I don't want to wait for a BTO, especially as I may have to take it back anyway due to apparent panel issues. So I'm tempted to get the upgraded version after all, that way I can always replace it quickly if need be. But my main concern is fan noise when doing moderate computing tasks like browsing, watching an occasional YouTube, listening to music, etc. For those tasks I want the machine to be pretty much silent. Thing is, I intend to use the unit often in clamshell mode driving an external monitor. From what I've read on these forums, when driving an external monitor the discrete GPU is always forced on. (I did read about that app gfxCardStatus that can force it to integrated, but I seem to recall reading that it won't work when driving an external monitor, that in such cases it will use discrete regardless). Can someone who has the discrete GPU version test it in clamshell mode driving an external monitor? In a silent room is fan noise noticeable (again with light/moderate tasks)? Thanks for any input.