The 2013 MacBook Air Review (13-inch)
by Anand Lal Shimpi on June 24, 2013 12:01 AM EST802.11ac: 533Mbps Over WiFi
Haswell isn’t all that’s new with the 2013 MacBook Air, Apple also integrated support for 802.11ac. I wrote a primer on 802.11ac last year, but I’ll provide a quick recap here. 802.11ac is a 5GHz-only WiFi standard, with support for wider channels (80/160MHz vs. 40MHz in 802.11n) and better spatial efficiency within those channels (256QAM vs. 64QAM in 802.11n). Today, that means a doubling of channel bandwidth and a 4x increase in data encoded on a carrier, which are responsible for the significant increase in bandwidth. Usable bandwidth should also see improvements on 802.11ac as high-end access points are all expected to ship with beam forming enabled.
The first 802.11ac implementations we saw were on the smartphone side with HTC’s One and Samsung’s Galaxy S 4. Both of these devices were single antenna/single spatial stream implementations with 80MHz channels and 256QAM, resulting in a max PHY rate of 433Mbps. In his review of the HTC One, Brian documented peak performance using iPerf and a TCP transfer. In a smartphone, such high bandwidth from WiFi is really useful for improving battery life (race to sleep). In a notebook, you get the same potential improvement in battery life but there’s one more: a wireless alternative to Gigabit Ethernet.
In a 3-stream configuration given what’s available today, we’re talking about a 1.33Gbps PHY rate. Assuming better link efficiency on a notebook compared to what we’ve seen in smartphones thus far, we could be talking about a real alternative to Gigabit Ethernet - at least close to an AP. While wired GbE is always going to give you a more consistent experience, the vast majority of homes aren’t pre-wired with Gigabit Ethernet. In living situations where you can’t just run a bunch of Cat6 everywhere, but still want high speed networking, 802.11ac could be a real alternative.
The 2013 MacBook Air adds support for 802.11ac via Broadcom’s BCM4360. The controller is capable of supporting up to 3 spatial streams, but in its implementation in the MacBook Air we see a maximum of 2 used. I fully expect the 2013 rMBPs to use a third antenna to leverage all 3 streams. BCM4360 supports 80MHz channels, 256QAM and short guard intervals. The result is a max PHY rate of 867Mbps.
ASUS sent me its RT-AC66U based on the same BCM4360 silicon (coincidentally the same controller that’s in the new Airport Extreme), which I promptly used for testing the new MacBook Air. The ASUS router and MacBook Air combination worked perfectly. In the same room as the AP, I had no issues seeing the maximum 867Mbps PHY rate (above).
Within about 5 - 8 feet of the AP, I saw an average of 533Mbps using iPerf. That’s real data sent over TCP:
A 3-stream solution could definitely rival wired GbE, at least for short distances.
I then went about characterizing 802.11ac performance vs. distance to get an idea for how performance fell off as I moved away from the AP. My desk and test area is in the corner of my office, which is where I put the ASUS 802.11ac router. Performance around my desk was always up around 533Mbps.
Move around 18 feet away but remain in the same room and measured performance dropped to 450Mbps. One set of walls and another 10 - 15 feet dropped performance to between 250Mbps - 340Mbps. Another set of walls without moving much further and I was looking at 200Mbps. When I went one more set of rooms away, or dropped down to a lower level, I saw pretty consistent falloff in performance - dropping down to 145Mbps. Note that my setup is pretty much the worst case scenario for longer distances. The AP isn’t centrally located at all. If I were setting up an 802.11ac network for max coverage, I’d probably see 300 - 400Mbps in most immediately adjacent rooms.
So 802.11ac on the new MacBook Air is pretty awesome, there's just one issue...
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JDG1980 - Monday, June 24, 2013 - link
I think we should have seen noise and thermal measurements, especially since this is Haswell. Will you be able to sit it on your lap without burning yourself? The desktop Haswell chips get nearly hot enough to boil water. I don't believe Intel's official TDP ratings for Haswell; the 4770K allegedly dissipated only 84 watts, but generated more heat than a 130W Sandy Bridge-E.Assuming you plan to use OSX (I can't stand it myself), the low resolution is a real killer. Windows is the only OS that has good font rendering at low DPI (via ClearType). On OSX everything is a blurry mess, and on Linux it's even worse. (Rendering at low DPI is much harder since they have to use a bunch of hacks like hinting and sub-pixel antialiasing to get the font to fit the pixel grid and look reasonably clear.)
It's disappointing to see Apple using Elpida RAM; it's far worse than Hynix or Samsung. And end users shouldn't expect to get the Samsung panel reviewed here; they will almost certainly end up with an inferior LG panel unless they return the system and complain. That's what happened with the rMBP last generation. The sales tactics came close to bait and switch, IMO: send out a good product to reviewers, then after a few months of sales, switch to inferior parts for future production without any indication on the packaging or labeling.
FwFred - Monday, June 24, 2013 - link
Temperature != heat. Also, there is no IHS on a mobile part, so the CPU die may directly be mounted against the cooling solution.mavere - Monday, June 24, 2013 - link
No IHS means no TIM issues means TDP has an extremely, extremely strong correlation to heat and noise, especially as teardowns show similar internal construction. Like the review said, TDP is respectably lowered in Haswell.>>> "It's disappointing to see Apple using Elpida RAM; it's far worse than Hynix or Samsung."
By what metric? Are you claiming that the RAM won't reach their rated speeds? Or are you claiming there's a pending RAM death situation here?
I would love citations in any case.
star-affinity - Monday, June 24, 2013 - link
Don't agree on OS X. It's great overall, once you get used to it. A good start is to not expect everything to behave like in Windows. Also don't agree on the font rendering. If you think it looks better in Windows I'm guessing you're not really into graphic design?tipoo - Thursday, November 6, 2014 - link
I think it does look better, I'm not a graphic designer. However I know OSX may have fonts that are more true to what they were designed as, Cleartype dramatically improves edges on low res displays and makes them bearable. Each pixel effectively becomes three pixels of resolution, so edges are much much smoother. OSX may have "truer" fonts, but chunky looking.A5 - Monday, June 24, 2013 - link
That 130W SB-E die is significantly larger than the 84W Haswell die. Once you add in the fact that more of that TDP is actually being used due to the on-package VRMs, it is pretty obvious why a Haswell would be hotter at the same loads.Paapaa125 - Monday, June 24, 2013 - link
I just used MBA 2011 11" model and the resolution is just fine. At normal viewing distances (30-40cm) the text look clear - no pixels. 135ppi at 40cm means one pixel covers 1,5 arcminutes. That is actually very small unit and quite close to eye resolving power. Definitely you can see the pixels when viewing closer but for normal distances the resolution is 100% sufficient for getting the job done.helloworldv2 - Monday, June 24, 2013 - link
I've been running some terminal stuff for multiple hours with the new i7 model (8GB RAM) utilizing 100% of both cores (4 cores with hyperthreading) and at no point the laptop got uncomfortable to hold on lap (bare skin)..akdj - Wednesday, June 26, 2013 - link
A) Thermal measurements. BS. You don't think the reviewer would've brought to our attention the fact he burned his lap while watching a movie? It's drawing less power at lower clock speeds...there isn't an expectation that the 'heat' on the outside would be anymore significant than the 11/12 core i models. Noise was commented on. In comparison to last year's model, it was quieter while rendering I believe. As well...he mentioned several times throughout the article his anticipation testing the i7 model when he's done flying around the world....yet still submitting a tremendous 'initial' over view or the new Airs. Believe Intel or not....these are 15watt chips. Not 85. Not 130. They're not gonna hurt ya bud.B) OSx. Now your comments are becoming a bit more clear. I use Windows 7/8 and OSx daily. Your comments on text are clearly based on 'what you've heard' and nothing to do with reality. In fact, my friend...'Tis Windows that has awful 'scaling' implementation when it comes to hiDPI displays....including any non native Windows software on the Surface pro. Very troublesome and hopefully will be addressed in 8.1. You're comments on a 'blurry mess' are nothing but BS. @ over 135 dpi on the standard 11" Airs, the resolution in relation to the size of the monitor are just fine! 1080p on that sized display without the same pixel doubling tricks used on the rMBPs would be truly unreadable for most folks over 12 years old! Seriously! I'm an Air and rMBP owner....as well as a PC high resolution display owner. While windows does have some benefits to 'ClearType'....OSx has NO issues with text display. While I'd like to so them step up to IPS, their TN panels, out of the box...have lead the industry for years. Objectively and subjectively. There is NO argument. Windows...on the other hand....they've got a way to go. ClearType isn't the answer. They'll need to implement the same trickery as OSx for text display on HiDPI monitors. No one can see, much less make use of a 2880x1800 display in native Rez. That's the cool thing OSx has managed to pull off....while pixel doubling for text...pics, video, and other creative work can be displayed @ it's native resolution while 'inside' an app using the pixel doubling for its interface. EG; photoshop, FCP....where you CAN have the entire 1080p, every pixel represented inside your canvas while the UI remains usable and crystal clear
Elpida RAM. You are awar that Apple has achieved near 100% efficiency now with their 'soldiered in' RAM. Something NO other user replaceable RAM system can compete with. There are no issues with Elpida...other than the fact you've not heard about them.
LG vs Samsung...very, very arguable. I ended up with an LG in one of our two rMBPs. In four months, image retention set in and Apple immediately replaced it. No questions asked. That said, LG is one of the Biggest and Best panel manufacturers in the world. LG panels in comparison to Samsung have shown better contrast, white and black point....and higher brightness. My Samsung is warmer, but calibrated I've got it pretty close to 6500°. LG is absolutely NOT 'inferior'. They changed out their original panel in the rMBP with an updated version. This is new technology, after all....there are going to be hiccups.
Your 'bait n switch' conspiracy theory is just that. As a small business owner....and as fa from a 'tech reviewer' as one could be....each of my rigs has performed in parity with reviewed models from sites like Anand. No different.
You're full of a WHOLE LOTTA hot air....and obviously have some sort of vendetta against Apple and OSx. Not sure why, maybe your mom said 'Absolutely Not!' When you asked if she would buy you one. Who knows...but quit with the drivel
gxtoast - Monday, June 24, 2013 - link
Fantastic article! However, I just wanted to hit something on the head that seems to be a common misperception:"...In living situations where you can’t just run a bunch of Cat6 everywhere, but still want high speed networking, 802.11ac could be a real alternative."
It seems that most people think that installing Cat6 will give them better 1Gbps Ethernet performance. It won't. Cat6 is irrelevant for 1Gbps. Cat6 is a 10Gbps standard. Cat5e is the 1Gbps standard.
Cheers :)