Review: Apple's 2011 Thunderbolt 11-inch and 13-inch MacBook Airs
Jump to a different section
What's new in MacBook Air hardware: Thunderbolt
The first notable new hardware feature of the 2011 MacBook Air is Thunderbolt, the high performance data interconnect developed by Intel that Apple incorporated into its Mini DisplayPort jack.
The addition of Thunderbolt allows the Air to connect to external drives at much faster rates than USB or Firewire. Thunderbolt is essentially an external implementation of PCI Express, enabling external break out boxes to incorporate interfaces for other data port specifications, including USB, Firewire and Gigabit Ethernet.
Thunderbolt is supported on the new MacBook Air models via an Intel E78296 01PB10 / E116A756 SLJ4K Platform Controller Hub chip, which replaces the Nvidia controller and graphics chip previous Air models used. The graphics processor of the new models is now integrated into the Intel Core i5 or i7 processor package itself.
Apple first added Thunderbolt to its MacBook Pro models in February, followed by the release of a Thunderbolt iMac in May. Alongside the MacBook Air, the company has also added Thunderbolt to its Mac mini this month, making the new data interconnect available across its entire consumer product line (apart from the yet to be refreshed Mac Pro).
At the release of the MacBook Air, Apple also announced its new $999 Thunderbolt Display, which connects to a Mac via Mini DisplayPort and provides a MagSafe connector for powering notebooks while in use. Unlike the previous Apple LED Cinema Display (review), the 27 inch panel uses Thunderbolt to provide a passthrough Thunderbolt port, a FireWire 800 port, 3 USB 2.0 ports, and a gigabit Ethernet port. This new offering provides the first Apple-supplied equivalent of a notebook dock for the MacBook Air, dramatically expanding its functionality beyond just being a light and thin notebook.
What's new in MacBook Air hardware: Sandy Bridge Architecture
The other major difference in the 2011 MacBook Air is the move to Intel's Core i5/i7 Sandy Bridge architecture. Apple first migrated its MacBook Pro notebooks from the Core 2 Duo architecture to Intel's Nehalem architecture in mid 2010, using Arrandale Core i5 and i7 chips. In February, the Pro line was upgraded to Sandy Bridge Core i5 and i7 chips.
However, the MacBook Air, like the entry level white MacBook, remained stuck with Core 2 Duo, primarily because of the added cost and heat dissipation of the latest core i5 and i7 chips. This summer, Intel released mobile "ultra-low voltage" versions of the Sandy Bridge architecture, finally making it possible for the MacBook Air to use the new chips without overheating, gaining significant weight related to the added cooling required, or losing significant battery life.
The new Sandy Bridge MacBook Airs are rated to last for 5 hours (11 inch) or 7 hours (13 inch). All MacBook Pros are rated for 7 hours of use, but pack in much larger batteries (rated at 63.5, 77.5, or 95 watt-hours for the 13, 15 and 17 inch models, respectively). The 11 inch Air has a slim 35 watt-hour battery, while the 13 inch Air uses a 50 watt-hour battery. The two Air models also provide 45 watt MagSafe power adapters, rather than the 60 or 85 watt power adapters required to charge the 13 or 15 and 17 inch MacBook Pros.
As previously noted, the migration to Sandy Bridge processors necessitates a move away from a dedicated Nvidia graphics processor, as Intel has incorporated its own graphics chip within the CPU package and blocked Nvidia from building supporting controller chips for its new CPUs. In addition to taking over graphics processor functions, the new mobile Core i5 and i7 processors also handle memory management, directly interfacing with the installed RAM.
This functionality was previously provided by the CPU's supporting controller chip, which Nvidia competed against Intel to sell, and which Apple preferred to use over Intel's own platform controller. While the increased performance and sophistication of Intel's Core i5 and i7 processors were enough to sway Apple to migrate away from the Core 2 Duo paired with Nvidia's controller chip, Intel's proprietary Thunderbolt interface, which is deeply integrated into the chip platform's architecture, will likely be enough to keep Apple from considering third party processors and controllers from Nvidia or AMD in the near future, outside of the high performance, dedicated GPUs the company continues to use in its MacBook Pro and iMac lines.
What else is new in MacBook Air hardware
While not connected to Intel's Sandy Bridge, the new MacBook Airs also incorporate support for the newly emerging Bluetooth 4.0 specification, aimed primarily at supporting low power peripherals. A teardown report by iFixit noted that the new Airs include a mini-PCIe wireless card powered by a Broadcom BCM4322 Intensi-fi Single-Chip 802.11 Transceiver and a Broadcom BCM20702 Single-Chip Bluetooth 4.0 Processor with Bluetooth Low Energy Support. The MacBook Air is Apple's first notebook to include support for Bluetooth 4.0.
The new MacBook Air models continue to provide standard FaceTime cameras (formerly branded iSight) rather than the higher quality FaceTime HD cameras sported by the MacBook Pro line. Using the Thunderbolt Display, Air users can switch to the higher quality FaceTime HD camera within the external display for full 720p video conferencing.
In other respects, including ports and other hardware features, the latest MacBook Air models appear identical to the previous generation apart from the Thunderbolt logo adorning the enhanced Mini DisplayPort jack (below) and the grey key labels hinting at the newly restored backlit keyboard feature.
On page 3 of 3: CPU Performance; BTO Options; RAM & Battery Performance; Mac OS X Lion; Rating; and How to Save When Buying.