Thunderbolt

We wrote about Thunderbolt when the new MBPs launched, and about the differences between when it existed as Intel's codename Light Peak like we used to know it and saw at IDF. Thunderbolt differs technically and in practice in a number of ways. The short version of the story is that Thunderbolt is Light Peak sans light in this initial form (electrical right now), uses the mini DisplayPort connector on the MBP, and is capable of two channels of full duplex 10 Gbps traffic, for a theoretical 20 Gbps up and down. Thunderbolt requires a controller on the host and peripheral, uses 4 PCIe lanes, and connects to Display Port internally on the MBP's discrete GPU. One of the interesting things is where those 4 lanes come from on the 2011 MacBook Pro.

Thunderbolt can supply 10 watts of power and support up to 7 devices, up to two of which can be DisplayPort 1.1a devices. Just PCIe and DisplayPort are tunneled over Thunderbolt links. However, you can connect a standard DisplayPort monitor to the jack on the MBP and use it natively as well.

Sandy Bridge brings 16 lanes of PCIe really purposed for running a GPU. Interestingly enough, the discrete GPU on the 2011 MBPs uses just 8 PCIe lanes:

So where do the remaining 8 lanes get used for? They're split into 2 x 4x ports, one of which is for Thunderbolt. It's surprising, but this configuration is totally supported. Originally I speculated that the other 4x lane was being used for another PCIe interface device in the MBP (the SDXC card reader and BCM7765 are both 1xPCIe devices), but it appears they're unused.


Intel's Thunderbolt controller

Thunderbolt launches with Apple, but isn't Apple exclusive. Intel reports that we just likely won't see adoption in the PC space until 2012. In addition, there's no per-port licensing fee or royalty for peripheral manufactuers wanting to use the port or controller, which are entirely Intel's. The controller is actually of appreciable size on the 2011 MBP:

Initially, Thunderbolt is electrical only, though the optical version of Thunderbolt is coming later this year. Optical cabling will be compatible with this electrical version through the use of electro-optical transceivers on the cable ends.

Bottom: 2011 MBP with Thunderbolt port, Top: 2010 MBP

We can't test and see whether Thunderbolt works or does anything right now, because there aren't any devices on the market with support. That said, Western Digital, LaCie, Promise, and other external storage manufacturers have stated that drives will arrive shortly, which we will surely take a look at. There are also rumors of various high end DSLRs shipping with Thunderbolt in the near future, though that's anyone's guess.

There's a field for Thunderbolt in system profiler, but even with a DisplayPort monitor attached, it shows nothing connected:

Interestingly enough, in Windows there's no trace of Thunderbolt at all. There aren't any unknown devices in the device manager, no device ID either. Hopefully Boot Camp drivers come along for Thunderbolt in Windows before devices start rolling out.

Improved WiFi Performance FaceTime HD Cameras
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  • iwod - Friday, March 11, 2011 - link

    iPad is only just starting to sell and iPhone still has lots of space to grow. The trend is Apple are making more units and more money from ARM specific products.

    Nvidia has just recently stated that Project Denver will be ARM 64 bit. And aiming at HPC and Desktop. Full Compatible with current ARM instruction set.

    Currently Apple must have a ARM version of Lion testing, and few years down the road, they could switch their Mac over to ARM 64 bit. Using a single Instructions Set for their whole product line.

    For some reason i have been thinking that Apple and Intel aren't doing too well together like anand has felt. I dont think Thunderbolt is any indication of their current relationship. it is merely they have been working on it for such a long time, no one wants to lose our at the end.

    Of coz it could have been the other way round x86 moving into iPhone, although that depends how much intel is willing to bend towards apple.
  • jbh129 - Friday, March 11, 2011 - link

    Anand,

    Can you guys run your high-end 15 through the Windoze tests that were used on the 13?

    Thanks
  • tajmahal42 - Friday, March 11, 2011 - link

    Hello guys!

    First, I have to say this review is really awesome, as usual! Just what I was hoping for. The thoroughness and practical sense of your reviews continues to amaze me every single time.

    For the 13" MBP, you mention "bouts of instability". Can you elaborate on that? Stuttering? Crashes? In what way do you notice that instability? I'm a little concerned now.
  • tno - Friday, March 11, 2011 - link

    +1
  • alent1234 - Friday, March 11, 2011 - link

    my wife has been bugging me about our wifi since we moved and get a poor signal in a lot of the new apartment. told her i can get a new router with 3 antennas but we will also need a new laptop as well with the antennas to take advantage of it.

    which brings me to my question. i know the 15" model has the 3 antennas. does the 13" do MIMO as well?
  • tipoo - Friday, March 11, 2011 - link

    They all use the new card.

    By the way, have you tried switching wifi channels, or installing DD-WRT and boosting signal? Even so, you don't need a new laptop after getting a new router if signal strength was the only problem.
  • alent1234 - Friday, March 11, 2011 - link

    i'll try that, thx

    a lot of wifi around me these days. we only have work laptops now so that would be our only personal computer if we bought one. i was looking for the cheap SB models when they come out
  • name99 - Friday, March 11, 2011 - link

    "told her i can get a new router with 3 antennas but we will also need a new laptop as well with the antennas to take advantage of it."

    This is not completely true. A base station with multiple antennas CAN do the equivalent of phase-array beam steering to direct most of the output power towards the target laptop. The laptop will thus see a stronger signal, and one of the better modulation schemes (eg 64-QAM 5/6) can be used rather than one of the weaker schemes. Thus your laptop, even if it has only one (or two) antennas can still see better performance.

    Note, this is a theoretical possibility. I do not know the current state of the art in how well base stations utilize the various forms of transmit diversity that are available. And no review ever seems to talk about this stuff, either by testing how well the kit works with a single antenna device, or by talking to the manufacturer about what's in their product.
  • Brian Klug - Friday, March 11, 2011 - link

    The 13" does have 3x3 MIMO as well, the exact same broadcom solution as the 15" I tested extensively.

    -Brian
  • 7Enigma - Friday, March 11, 2011 - link

    Anand and crew,

    I am very disappointed with the battery life numbers in this review. This is the first review of a laptop where it appears you have used a 3rd party app (Cody Krieger's gfxCardStatus tool) to significantly inflate the numbers of the new 2011 systems. 35-60% by your own numbers back on the discrete GPU battery life page, which you then fail to report in the battery life tables later on!

    When you are tasked to review a system (especially an Apple product I might add) it should be reviewed as is, with no tweaking or 3rd party add-ons to boost performance/benchmarks. When have you EVER installed an add-on for a Windows-based laptop to improve performance/life? I can't think of one.

    At best this was a simple oversight where you have benchmark numbers WITHOUT the gfxcardstatus, at worst this was a cover-up job which I have always argued in the forums against and on your site's behalf.

    Please update the tables to show what a stock newly-purchased laptop at the Mac Store would deliver.

    I am very disappointed in this coverage.

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