The Apple Thunderbolt Display Review
by Anand Lal Shimpi on September 23, 2011 2:56 AM EST- Posted in
- Displays
- Mac
- Apple
- Thunderbolt
- Thunderbolt Display
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.
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.
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CharonPDX - Friday, September 23, 2011 - link
I had HOPED to buy either a Mac Mini or a MacBook Air this year. Finances aren't allowing that.But, it looks like sometime mid next year, I should be able to upgrade.
At this point, if Anand's wish comes true:
I'll be getting an 11" Ivy Bridge Air and a Thunderbolt Display.
Death666Angel - Friday, September 23, 2011 - link
"capable of at least 350 nits at full brightness"Just wanted to say that Apple actually advertises 375 cd/m² on their website. :-)
tzhu07 - Friday, September 23, 2011 - link
I wish Anand would've addressed the issue of the glossy-only screen option in the video review. Why did Apple and some others continue to seemingly promote this type of screen? There are many people that consider it a deal-breaker, including myself. How much of a hassle is it for Apple to have two variations of the same product?repoman27 - Friday, September 23, 2011 - link
"While the display does feature a pair of integrated speakers, they don't produce the best sound in the world. Thanks to their diminutive size and unusual enclosure, the speakers don't cover a lot of dynamic range and you can forget about any ultra low frequencies. If you like bass, you still need a sub."According to Apple's specs, the ATD has a 2.1 speaker system, so it already has a sub of sorts. Also the claimed power for the audio system is 49 watts, which is pretty staggering for something built into a display. Actually it's good compared to most compact PC desktop speaker systems. It's too bad that it impresses more on paper than it would seem to in real life.
dunce - Friday, September 23, 2011 - link
Can I use that Thunderbolt port on the back to plug in a second computer (MacMini/PC)? I am looking at this and the Dell 27in but would like multi computers inputs.Constructor - Saturday, September 24, 2011 - link
No, as far as I'm aware there can only be one master (CPU) on a Thunderbolt chain.kalistan919 - Friday, September 23, 2011 - link
Will Thunderbolt connections be available for the new 28nm gpus that are coming from AMD and Nvidia? Or will Ivy Bridge channel your discrete gpu from the gpu to motherboard to display through a thunderbolt connection on the motherboard? Does anyone know if Apple will come out with a 30" Thunderbolt Display like they did just recently with the 27" display?These are three questions I tried to find but couldn't. Here's another one...would a minidiplayport on the GPU card work with an apple thunderbolt monitor? Anyone have the lowdown on this? Thanks in advance.
ggathagan - Saturday, September 24, 2011 - link
The GPU's themselves do not dictate what type of connection is used; that's up to the video card manufacturer.Remember, however, that Thunderbolt is not a GPU-specific interface, so a discrete video card with a TB connection would require the manufacturer to add the TB controller and its associated circuitry to their video card.
I doubt that'll happen.
Ivy Bridge will not have integrated TB, so the answer to your 2nd question is also "no". The motherboard would have to take the video output, whether from the CPU or from a discrete GPU, and route it through an on-board TB controller.
30" displays are going away in most market sectors, so I doubt you'll see a 30" with Thunderbolt.
More specifically, I doubt you'll see *any* 30" display from Apple in the future.
As to your last question; from the article:
"A Thunderbolt cable can only transmit a Thunderbolt signal. Although DisplayPort is muxed in, if the display on the other end is expecting Thunderbolt and it receives DisplayPort it won't know what to do with it. It's possible Apple could have built in logic to autosense and switch between Thunderbolt and DisplayPort as inputs, but Apple traditionally employs clean breaks rather than long technology transitions. If Apple wants to ensure Thunderbolt gets adopted (at least by its users), this is the way to do it. "
According to this discussion at Apple's site, someone tried using a non-TB MBP and MBA and were not successful.
https://discussions.apple.com/thread/3199231?start...
What I would expect to see is someone marketing a Thunderbolt adaptor that converts a DP input to TB output.
In fact, I would expect to see Apple create this eventually, but it'll be atrociously expensive from them.
Since the whole point of TB is the ability to bundle multiple types of data traffic through a single interface, the only scenario where using a TB-equipped monitor currently make sense is one like this article describes; as an alternative to a docking station for a laptop.
It *would* make sense for a display manufacturer to make a TB-equipped monitor that could auto-sense with the input is DP or TB, but only if you're taking the same approach as Apple and include LAN, USB, audio and FireWire connectivity in the monitor.
If, for instance, Dell were to create a line of TB-equipped monitors with all the connectivity I described above, they could market those monitors in conjunction with a TB-equipped desktop and/or laptop series.
The desktops would only require the TB cable and a power cable; the monitor would handle all the peripheral connections.
Essentially, however, you end up having to decide if you want all your connections at the monitor or at the computer itself.
Historically, people prefer to limit the number of cables hanging off of their monitors and leave the rats nest at the computer.
Where I think TB hold the most promise in relation to desktop systems is in the area of external storage, like the Promise Pegasus Anand mentioned.
Impulses - Saturday, September 24, 2011 - link
Usually I skip video reviews entirely unless it's something that's just not communicable easily in text (factory tours and game trailer for instance)... They just tend to ramble on and/or provide very little info.However, the video on the first page of this review was excellent! You should've started doing these long ago, I actually read the entire review first even tho I'm not even remotely interested in the display (I am curious about Thinderbolt's future tho), and I started front to back as I often do (by reading the conclusion first and then skipping to other interesting parts). Having read the whole thing previous to watching the video I feel like the clip actually did a better job at summing it all up than the conclusion or Final Words, which is very impressive, great job!
ppayne - Saturday, September 24, 2011 - link
I'd love to see mods for this appear. Imagine 2 2.5 inch hard drives wired inside somehow and accessible through Thunderbold?