Wondering if others have experienced this... When I run my MacBook Pro 15" Late 2013 w/ the built-in display + iMac 27" TDM (2560x1440) + Apple Cinema Display 23" (1920x1200), the machine eventually works hard enough, runs hot enough, and blasts the fans full enough that the battery level actually DRAINS while it is plugged in. So, presumably, after a long enough session like this, the MacBook would simply run out of sufficient power and shut down. Although this admittedly isn't a common scenario, it does seem like a bit of an "Oops...oh well, f*ck it" in design/testing. Anybody else observe this phenomenon? Suggestions for making this work more efficiently? iStat shows the GPU is clearly running hottest and obviously causing the fans to ramp up to full speed. The 2 external displays' total add'l pixels (~6 million) equate to an increase of approximately 115% over the built-in Retina panel alone...still a good bit below what a single 4K display would add (~8.3 million pixels)... Thx, Fred --- Post Merged, Mar 28, 2018 --- Interesting comparison: just removed my Late 2013 MBP15 from the aforementioned arrangement and inserted my secondary Mid 2015 MBP15 w/ only Intel Graphics in its place. The 2015 has less "stuff" running, so it has a little bit greater percentage Idle in Activity Monitor, but the fans have barely come off their idle speed of 2000rpm (one is at 2K, the other at 2200rpm). As you'd assume, the battery stays at 100%.