The 2011 MacBook Air (11 & 13-inch): Thoroughly Reviewedby Anand Lal Shimpi on July 28, 2011 3:25 AM EST
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- Sandy Bridge
- MacBook Air
A New Thunderbolt Implementation
The other major change to the new MacBook Air is support for Intel's new Thunderbolt interface. We first met Thunderbolt on the 2011 MacBook Pro and saw it again on the iMac. Both the new Mac mini and the MacBook Air now support Thunderbolt as well, although the Air's implementation is slightly different.
If you look at iFixit's teardown of the new 13-inch MacBook Air you'll notice the absence of the traditional flip-chip Thunderbolt controller from the MacBook Pro, iMac and Mac mini. In fact, there are only two flip-chip parts on the motherboard - the Core i5 and the QS67 chipset.
13-inch MacBook Air (Mid 2011) Motherboard, QS67 (left), Intel Core i5 (right) - Courtesy iFixit
iFixit assumed that the QS67 chipset integrated Intel's Thunderbolt controller. Unfortunately there are a couple of things wrong with this assumption. First off, Intel has already announced that Thunderbolt wouldn't even be integrated in Ivy Bridge chipsets next year. While it's possible that Apple could request a special chipset from Intel, Apple would have to pay for the added design, manufacturing and validation costs or commit to huge volume numbers in order to make the effort worthwhile for Intel.
The second problem with the assumption has to do with the QS67 die itself. It looks unchanged from the square 6-series chipset die we saw back at CES earlier this year:
I didn't measure the two but they do look awfully similar. It's far more likely that the Thunderbolt controller is simply elsewhere on the motherboard. But where?
In all existing Thunderbolt Macs, the controller is very close to the Thunderbolt port. Looking carefully at the new MacBook Air you'll notice a tiny Intel chip near the Thunderbolt port:
Intel's Eagle Ridge SFF Thunderbolt Controller - Courtesy iFixit
This is a brand new Thunderbolt controller from Intel - codenamed Eagle Ridge. The chip used in the MacBook Pro, iMac and Mac mini is called Light Ridge and it looks like this:
Light Ridge Thunderbolt Controller IC on 15" 2011 MacBook Pro - Courtesy iFixit
Light Ridge supports four bidirectional 10Gbps channels (20Gbps total per channel) channels and two DisplayPort inputs/outputs. On the iMac it's used to drive two ports on the back of the system.
Eagle Ridge is half of Light Ridge. You get two bidirectional 10Gbps channels (20Gbps total per channel) and one DisplayPort input/output. Eagle Ridge is offered in both a normal and small form factor package, the SFF version is what's used in the MacBook Air. I suspect Eagle Ridge is the cost reduced version of Intel's Thunderbolt controller Apple needed to maintain profit margins while bringing out a $999 MacBook Air with Thunderbolt.
Both the 11 and 13-inch MacBook Air have a single Thunderbolt port. This port is on the right side of both machines in the same location as the miniDP receptacle in last year's model.
The Thunderbolt port on the new 11 (top)
I already mentioned that functionally Thunderbolt in the MacBook Air is no different than in the MacBook Pro. A quick visit to Windows 7's device manager confirms that the Thunderbolt controller branches off of the CPU's on-die PCIe controller:
The unidentified RAID device is a Promise Pegasus R6, which still lacks driver support under Windows. With no discrete GPU in the MacBook Air there are more than enough PCIe lanes for Thunderbolt, but this controller still only uses (and needs) 4 of them.
Both DisplayPort and PCIe are carried over to the Thunderbolt port on the system. Apple clarified that you can in fact mix video and PCIe traffic on a single channel or across multiple channels. This gives you 20Gbps of upstream bandwidth and 20Gbps of downstream bandwidth to use however you want. Remember that driving a single 27-inch 25x14 display uses up around 7Gbps of upstream bandwidth alone, but there's still more than enough for storage and other needs.
I tested the Pegasus R6 with both MacBook Airs and its performance was similar to the MacBook Pro:
|Promise Pegasus R6 12TB (10TB RAID-5) Performance|
|Sequential Read||Sequential Write||4KB Random Read (QD16)||4KB Random Write (QD16)|
|15-inch MacBook Pro (Early 2011)||673.7 MB/s||683.9 MB/s||1.24 MB/s||0.98 MB/s|
|13-inch MacBook Air (Mid 2011)||647.4 MB/s||724.9 MB/s||1.38 MB/s||1.37 MB/s|
|11-inch MacBook Air (Mid 2011)||627.6 MB/s||723.3 MB/s||1.37 MB/s||1.37 MB/s|
Write speeds were a bit higher but I suspect that has more to do with changes to performance under Lion than anything inherent in the hardware.
Thunderbolt devices appear under System Profiler the same way they do on the MacBook Pro:
The Thunderbolt port can also function as a miniDP output which works as expected on the Air. UI performance is ok on a 27-inch Cinema Display driven by a MacBook Air despite the lack of a dedicated high speed frame buffer. The biggest issue is that firing up Mission Control or swiping between Spaces is met with a significantly reduced frame rate. If you're going to be using a high resolution external panel regularly, you might want to consider a MacBook Pro with a lot of dedicated video memory.
Note that the Air can only drive a single external display. Not only does the Eagle Ridge Thunderbolt controller only support one DisplayPort output but Intel's HD 3000 GPU only supports two display outputs and one is already occupied by the Air's panel.
The Thunderbolt Display
Neither MacBook Air has an integrated Ethernet controller, there's no need as neither system is physically thick enough to accommodate a standard RJ45 connector. Apple has sold a USB 10/100 Ethernet dongle in the past for MacBook Air owners, but these days you can get better performance over good WiFi than you can from 100Mbps Ethernet. This is where that magical Thunderbolt port comes into play.
Remember Thunderbolt is just a carrier for PCI Express and DisplayPort. Any device that lives off of a PCIe bus can in theory be used over Thunderbolt. Typically your GigE controller is a PCIe device that resides on your motherboard. Sonnet took a PCIe Gigabit Ethernet controller, put it in a small box along with a Thunderbolt controller and built this:
The Presto Gigabit Ethernet Thunderbolt Adapter is all you'd need to add GigE support to the MacBook Air. Need FireWire 800 support? Sonnet announced one of those too:
There's a total of 20Gbps of bandwidth in either direction over Thunderbolt, which is more than enough for 1Gbps of traffic over Ethernet or 800Mbps of traffic over Firewire. Availability is slated for "this summer" for both of these devices.
Rather than building individual cables, Apple did almost exactly what I asked for and built a monitor with more IO. It's called the Thunderbolt Display and it features an integrated USB 2.0, FireWire 800, Gigabit Ethernet and audio controller. All of these controllers reside on PCIe and are tunneled over to the host Mac via a single Thunderbolt cable.
While the MacBook Air doesn't support FireWire 800 or Gigabit Ethernet, paired with a dongle, breakout box or Thunderbolt Display you can add those options presumably without giving up performance.
This is what Thunderbolt was meant to do. All we need now is widespread adoption, more accessories and a standard for external GPU form factors.
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darwinosx - Saturday, July 30, 2011 - linkThere is barely any difference between Elitebook models to talk about. Nor is there anything particularly special about them. Just another Windows clone made and supported a little better than what HP sells at Best Buy. Given that, it was covered quite well.
OCedHrt - Thursday, July 28, 2011 - linkThis is so last year. This is not even what I got in my Sony Z last year. For $1600. 2.4 ghz i5 (520m), GT 330M in 3 lb chasis with internal dvdrw. And that was bottom of the line. Not to mention I got mine from MSFT with 40% off.
This year: http://store.sony.com/webapp/wcs/stores/servlet/Ca...
Of course this one costs way more, but still worth a though.
beginner99 - Thursday, July 28, 2011 - linklol yeah. Sony is the only brand that has even more ridiculous pricing than Apple. You say it yourself 40% off. And in this case I say apple's pricing is very competitive and I'm an "apple-hater". Never owned a single device from them, not even an Ipod.
The new base model Vaio Z will also be about 40% more expensive at half of the SSD capacity.
Anyway, I would have already bought it, if it was a windows system.
Johnmcl7 - Thursday, July 28, 2011 - linkI wouldn't say Sony's pricing is ridiculous as you're paying for absolutely cutting edge tech whereas with Apple . The previous Z series may have been pricey but it featured a 13.1 1080p screen (genuine 1920x1080), up to an i7 dual core processor, quad SSDs in RAID 0, dual graphics graphics cards (one integrated, one discrete), blu-ray writer which even Apple's 17in machines couldn't match but was smaller and lighter than Apple's 13in machines.
I have the Vaio from the previous generation (Z5) which has a C2D 3Ghz processor, 13.1 1600x900 screen, dual 128GB mSSDs in RAID 0, blu-ray writer and integrated & discrete graphics cards which again Apple didn't offer anything even remotely comparable. Speccing up a Macbook to the maximum level put it far above the Vaio in cost but far below in spec with just a 2.6Ghz processor, DVD burner, single graphics card and low resolution screen.
darwinosx - Saturday, July 30, 2011 - linkKids, read the review and learn something before commenting. No Sony has this proc in it yet. Also learn something about cpu speed in different processor models. Finally try to understand that this laptop is meant to be super thin and lightweight which the Sony is not. It is also top quality construction support and uses a modern OS.
OCedHrt - Tuesday, August 2, 2011 - linkThe sony from last year is nearly the same weight at 3.1 lb with an internal optical drive and the new one this year is much lighter at 2.5 lbs with external.
The Sony Z specifically do not use ULV processors for maximum performance:
Intel® Core™ i5-2410M processor (2.30GHz) with Turbo Boost up to 2.90GHz
Intel® Core™ i5-2540M processor (2.60GHz) with Turbo Boost up to 3.30GHz
Intel® Core™ i7-2620M processor (2.70GHz) with Turbo Boost up to 3.40GHz
The base processor already matches the top of the line Air processor in turbo and far exceeds it in other conditions.
So to recap: Sony Z from last year (Z11-Z14) is already super thin and light weight at significantly faster performance for same cost, and sometimes cheaper when Microsoft Store has a crazy sale.
Sony Z for this year Z21 is even thinner and lighter at even faster performance for a slight premium. Remember the lowest Z performs better than the fastest Air. $1969 vs $1599 gives you an external dvdrw and discrete graphics and usb 3.0. That's not a bad deal at all.
Keep in mind the fastest Z will kill the Air in performance all in the same chasis. And battery life from reviews indicate the new Z is on-pair with Air (4+ hours with a movie playing continouously).
OCedHrt - Tuesday, August 2, 2011 - link$1600 was not 40% off. I got mine for $1100. $1600 is the retail price at B&M for the entry level model that I outlined (with 64gb x2 SSD).
ViRGE - Thursday, July 28, 2011 - linkLooking at the specs, something doesn't make sense. They're using 35W TDP processors and claiming better battery life on a smaller battery than the 13" MBA. The math doesn't add up on that one.
KPOM - Thursday, July 28, 2011 - linkMight Sony be including the optional "sheet battery" in that time?
ViRGE - Thursday, July 28, 2011 - linkNope. They break that out separately.