Thunderbolt Performance

The Eagle Ridge Thunderbolt controller is home to two Thunderbolt channels, each one is good for up to 10Gbps in either direction (up or downstream). That works out to be 20Gbps of bandwidth per channel or 40Gbps aggregate between the two. You can only send two channels worth of data down a single Thunderbolt cable, so there's no point to having more than two from a performance standpoint unless you have more than one port on your system.

If DisplayPort and PCIe traffic are indeed carried on separate channels, then the Thunderbolt Display by itself is eating up around 70% of the bandwidth of a single channel on its own (2560 x 1440 x 32bpp x 60Hz with 8b/10b encoding > 6.75Gbps). That leaves 10Gbps in each direction for PCIe traffic. If we look at our benchmarks from the previous section we see that we can hit just under 2Gbps with all of the auxiliary interfaces (GigE, FW800, USB2) running. Given our previous investigation with the Promise Pegasus we know that 8Gbps is feasible there as well. It's possible, that with everything running at once, we could actually run into bottlenecks with Thunderbolt.

To find out I ran a few tests. First I needed a baseline so I threw four SF-2281 SSDs into the Pegasus R6 chassis and configured them in a RAID-0 array. I ran a 2MB sequential read test (QD=16) and measured 909MB/s from the array. This value was obtained without the Thunderbolt Display connected, only the Pegasus R6.

Next I connected the Thunderbolt Display directly to my test MacBook Pro, and then connected the Pegasus to it. I repeated the test, this time getting 900MB/s. Thankfully the presence of the Thunderbolt Display doesn't seem to impact the max data rate I can get from the Pegasus.

For my third test I added a Gigabit Ethernet transfer from a file server to a local SSD using the GigE port on the display. During this test I was also playing back music using the Thunderbolt Display's internal audio codec and speakers. I re-ran the Pegasus test and got 855MB/s.

For my final test I re-ran the third test but added a FireWire 800 to USB 2.0 SSD transfer, both connected to the Thunderbolt Display. I also fired up the FaceTime HD camera on the display using Photo Booth and left it on during the test. The final performance score from the Pegasus was 817MB/s.

Apple Thunderbolt Display Performance

With everything running Thunderbolt performance took a 10% hit. Note that the standard Pegasus configuration isn't able to hit these data rates to begin with, so unless you've pulled out the 12TB of storage and stuck in your own SSDs you won't see any performance drop.

What this does tell me however is the ultra high end users that are looking to daisy chain multiple Thunderbolt storage boxes together may not want to do so. I only have a single Pegasus R6 on hand, but I'm guessing there will be significant performance drop off after the first box. Not that I'm complaining about being able to push nearly 1GB/s over a $49 cable from a notebook, I'm just trying to give a heads up to those who may have aspirations of even higher performance.

Testing the Pieces Display Testing - Color Quality & Uniformity
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  • NCM - Friday, September 23, 2011 - link

    At under a grand for a giant IPS display that incorporates at least $200 worth of extra connectivity (laptop power supply, T'bolt, additional ports, speakers) this monitor is good value for a MacBook Pro or Air user.

    Colour accuracy is more than adequate for most professional work. If it's not good enough you should be taking a big step up to something like an Eizo, both shrinking the display size and doubling the price in the process.
  • jecs - Friday, September 23, 2011 - link

    You did read but you just don't understand what color accuracy means or what to do with it.

    What you call poor color accuracy is the gamut space that is important only if you work with wide gamut color. Apple does not cares for wide gamut, not with this display or with past displays. It does not means the display is not accurate in color, it is very accurate. But Apple optimize their displays for print accuracy were wide gamut is not required. Even for FCP Apple doesn't work with wide gamut. For consumer use wide gamut is also a mixed bag because many complain the color in general looks to bright or "artificial".

    I have a 2410 Dell display because I care for wide gamut for what I do but I do appreciate Apple displays and this thunderbolt display is good and other vendors should pay attention to the connectivity and function for desktop use. I would want a mate screen version for more serious professional design but for demanding consumers who appreciate quality and efficiency this is a nice option.

    But right now what you need to know is what display is best for what you do.

    Are you a professional. Are you a consumer or an aficionado looking for an intermediate option. Or buying the cheapest display.

    The Apple displays are for entry level professionals or high end consumers or hobbyist.

    For broadcast professional work or for cheap options look else where.
  • hechacker1 - Friday, September 23, 2011 - link

    While I agree with your overall point, I don't think the calibration used by Anand is really informative unless you are doing photo processing work.

    He's targeting the Adobe 1998 profile, which is great for photo editing and printers that support that target (rare unless in a professional setting).

    Most of the Internet is SRGB profile by default, and I'm guessing this display would perform even better there. Most consumer cameras also target SRGB unless you are talking about RAW mode prosumer cameras.

    The fact that this display can accurately display most of the Adobe profile bodes well for its accuracy.

    If you were in Broadcasting or video editing, you should target Rec. 709 profile, which has completely different gamma curves.

    In my opinion, Apple displays are generally very good for the money. Even my late 2009 Macbook Pro can calibrate to excellent color accuracy with VERY little error.

    However, my biggest complaint is that lately Apple displays target 6800-6900K color temps, which are too blue for most calibrations and profiles. Sure it looks good to the untrained eye, but it's bad for color accuracy.
  • jecs - Friday, September 23, 2011 - link

    I agree to your more expert opinion than mine.

    Apple is moving more than ever to the high end consumer or prosumer and the move to the higher kelvin could be another sign. Final Cut X and the price is another example.

    But all in all Apple displays are still good monitors.

    If you want a very cheap desktop IPS panel Dell also has a new Ultrasharp line with a shorter gamma space and fewer connectors. But there are other cheap options.
  • Ratman6161 - Friday, September 23, 2011 - link

    ...that I would not be in the market for a $1000+ display from Apple, Dell or an other manufacturer. What i'm in the market for is the best I can get for $200 - $300. Now, what I can get for my dell is a docking station that comes with an additional power brick for $129.00. So I can get a decent (not great but decent) 22 to 24 inch display + a docking station well within my budget.

    I guess if a 27" is what you absolutely have to have and you are willing to pay for it, this is a good option...but not for me.
  • NCM - Friday, September 23, 2011 - link

    Which is fine and all, but the fact that you aren't in the market for a monitor in this category is completely irrelevant to the discussion.

    What's next, that we start posting about our cats?
  • BrooksT - Saturday, September 24, 2011 - link

    Why would you spend $200 on a monitor when you can get a legal pad and pen for $8? I guess if you have to have a computer monitor and you're willing to pay for it, but paper and pen are better options for many people.
  • name99 - Friday, September 23, 2011 - link

    Professionals pay for quality tools.
    Look, if you're earning $100K a year, and this makes you more productive (not to mention happier) it's worth it.

    Are you amazed that professional carpenters don't use $5 saws from Target? That professional truckers rig up the insides of their rigs with fancy electronics? That professional musicians buy high quality instruments, not what they can find on Craigslist?
  • seapeople - Friday, September 23, 2011 - link

    You can also buy a $60,000 Cadillac Escalade SUV to pick up your kids at soccer practice.

    What's your point again?
  • alphaod - Friday, September 23, 2011 - link

    Nice review as usual; very tempted to purchase one, but I think I'm fine with my current setup; already have a power supply I keep plugged in at times.

    Honestly if Apple added a powerful GPU, yes I think it would a more enticing purchase, but than they'd have the issue of cooling this unit, powering this unit, and constantly upgrade GPUs; at the same time, we'd have people posting online asking all day when the next Thunderbolt GPU updates will come. This would probably also cause problems with pricing; it would come awfully close to the price of an iMac which I'm sure most people would then consider buying an iMac instead (making this product redundant).

    Personally I'd prefer if Apple added an optical drive (for those of us who replaced the optical drives in our MacBook Pro notebooks), optical out, better GPU in the display~Hell forget about releasing this display; redo the iMac as a dock for the MacBook Air/Pro!

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