Dual External Displays are a No-Go on MacBook Air 2011 via Thunderbolt
One of the more exciting features of the new MacBook Pro 15″ and 17″ and iMac series is that you can use dual external displays by daisy chaining them via the Thunderbolt port. Unfortunately, this ability is lost on the 2011 MacBook Air, due to the weaker Intel HD 3000 graphics chip and a stripped down Thunderbolt controller.
This was noticed by Anandtech, who points out the lightweight Thunderbolt chip, called Eagle Ridge, only supports a single DisplayPort channel compared to the dual channels in the larger Light Ridge chip:
Eagle Ridge is available in two form factors (normal and SFF) and is effectively half of a Light Ridge chip. That means you only get two Thunderbolt channels and one DP output. Apple used the small form factor version of Eagle Ridge in its new MacBook Air to cut cost and save on motherboard real estate.
While this may affect some purchasing decisions and direct a few users to the MacBook Pro line instead, not all is lost. The 27″ Thunderbolt Display with it’s whopping 2560×1440 resolution is a giant on it’s own and should be more than adequate to meet the needs of most users looking for external displays with their MacBook Air. Plus, Apple is openly advertising the Thunderbolt display as a docking station of sorts for the MacBook Air, since it brings FireWire, three additional USB ports, Ethernet, and a FaceTime HD camera.
And really, when we consider the heaviest MacBook Air is 2.9lbs and the benchmark performance is through the roof, can we really complain much?