Apple may be putting Thunderbolt in all of their machines these days, but not all of their machines are getting pure, unadulterated Thunderbolt. According to research done by AnandTech the MacBook Air only supports half the data channels of the chip found in other Apple models, as well as a single DisplayPort output.
Long story short, the MacBook Air can only handle one of Apple’s Thunderbolt displays, despite the displays being able to be daisy chained together.
Why the difference? Apparently the newer chip, named Eagle Ridge, comes in a smaller form factor, making it the prime candidate for machines that require their innards to be as compact as possible. The Eagle Ridge chipshet is built to only allow one Display output and fewer Thunderbolt channels for shunting your data (down to two from four).
It’s probably not going to matter much to many consumers considering the large price tag associated with Thunderbolt displays ($999), but as we start moving into a more Thunderbolt oriented world, MacBook Air users could find themselves a little at a disadvantage when it comes to plugging in peripherals and other Thunderbolt equipped products.
If you’re hoping to run two Thunderbolt displays and plan to really take advantage of everything the technology has to offer, you may want to consider a MacBook Pro over the MacBook Air at this point.
Honestly, this probably won’t affect too many people. Most people won’t use one Thunderbolt display, let alone two.