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Retina 5K iMac Will Not Act as External Display, Standalone Apple 5K Display Unlikely Soon

At Apple's introduction of the new 27-inch iMac with Retina 5K Display, Phil Schiller noted that the machine's $2499 starting price compares favorably with some of the higher-end 4K displays on the market today for closer to $3000, leading some to wonder whether it would be feasible to use the iMac as an external display for something like a Mac Pro.

For a number of years, iMacs have supported a feature known as target display mode, which allows them to serve as external displays for other computers, but as pointed out by TechCrunch's Matthew Panzarino yesterday, the new Retina 5K iMac does not support this mode.

imac_retina_waterfall
The probable reason for this is also likely the reason why Apple did not announce a standalone Retina Thunderbolt Display yesterday: bandwidth limitations. The current DisplayPort 1.2 specification used over Thunderbolt 2 on Apple's latest Macs simply isn't capable of handling the bandwidth necessary for 5K video over a single cable.

As a result, no current Mac, including the Mac Pro and Retina MacBook Pro models that do support 4K displays, can currently drive a 5K external display. Technically, Apple could allow another Mac to output video at a lower resolution and have the Retina iMac scale the content up to fit its display, but this would not be ideal and Apple has apparently elected not to support it as an option.

As noted by Marco Arment, simple plug-and-play support for 5K external displays over a single cable will need the new DisplayPort 1.3 standard, but that won't be an option until Intel's Skylake platform, the successor to the upcoming Broadwell family, is launched.
Doing it right will require waiting until DisplayPort 1.3 in Thunderbolt 3 on Broadwell’s successor, Skylake, which isn’t supposed to come out for at least another year — and Intel is even worse at estimating ship dates than I am, so it’s likely to be longer. [...]

I’d estimate — granted, I’m wrong a lot — that Apple won’t ship a standalone 5K display until at least 2016, and it won’t work with any of today’s Macs, including the 2013 Mac Pro.
Arment points out that Dell's upcoming 5K display uses dual DisplayPort 1.2 cables for connectivity but that no current Macs appear to support the setup and even if they did performance would likely not be ideal.

Another potential product on the horizon is a Retina 21.5-inch iMac likely at 3840 x 2160 pixels, although it is unclear when Apple plans to launch such a machine. KGI Securities analyst Ming-Chi Kuo predicts a second half of 2015 launch for the machine in a similar pattern to that seen with the MacBook Pro, where the larger 15-inch model received a Retina display option a number of months before the 13-inch model followed suit.



Top Rated Comments

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24 months ago
best product pipeline in 25 years my ass
Rating: 36 Votes
24 months ago
This sucks. I want a TB 5K now for my MacPro!
Rating: 21 Votes
24 months ago
Best you can get today?

For my Mac Pro I went with a 24" Dell UP2414Q 4k display. 4k at larger sizes than 24" is just awkward: pixels too big to use at 2x, too small for 1x. But this Dell is just the right size to be a Retina display that works TODAY.

It looks terrific! And it has nice scaling options just like a retina MacBook Pro. No software to install--Apple supports this model specifically with scaling options not found on larger 4k displays.

However... you get what you pay for with Dell. Styling-wise this is not Dell's worst (clearly imitating the 2007 black-and-aluminum iMac design), but it is NOT close to Apple's display standards:

- No camera, no mic, no speakers, no Thunderbolt hub, audio ports, Ethernet, etc.; no powered USB, just an unpowered USB hub that loses power when the display isn't on.

- No option to adjust brightness automatically with an ambient light sensor. (Didn't realize how much I'd miss that.)

- Won't reliably wake from sleep!! And when it does wake, sometimes you get only half the screen. Keep trying.

- A few little bits of hair or dust between the layers. Looks like dead pixels, but it's not.

- Cheap painted silver plastic, combined with a few not-quite-matching thin panels of real aluminum.

- Gaps and cracks and creaks and flexes. Just feels cheap.

- Awkward touch controls that don't always work. Sometimes you have to press hard. Simply adjusting the brightness is a pain.

- Unreliable sensor that makes the controls' lights blink annoyingly.

- No protective glass--and thus risky and difficult to clean, and easy to bash with a box corner.

- Can't respond to the brightness keys on my keyboard.

- Shipped at an awful 30Hz and took research and hoop-jumping to enable 60Hz.

- Good warranty that might help with some of the above... except it's unbearably painful to deal with their support staff. Good luck with that.

- No magsafe to power your Mac laptop. This is not a dock for a MacBook the way Apple displays can function; but that's OK with a Mac Pro.

- Not a great black level, and uneven glowing backlight bleed around the edges when viewing dark images. Viewing angle is OK, not great.

- Generates a TON of heat! Ouch! My electric bill!

- Sits on a permanent, very slight diagonal in landscape (normal) mode: the portrait–landscape pivot won't quite rotate all the way to level.

But yet... when viewed head-on, it has awesome res and color! I'm glad I have it--there is no better option yet. Also, it goes to Portrait... sometimes. And it can go very bright! And if you play endless games looking for deals like I did, you can find a cheap price. (Or you can get sent the wrong thing and waste time and end up not getting such a good price... like I did.)

I use mine at a scaled res equivalent to 2304x1296. But it will go as high as 3008x1692 if you like to squint.
Rating: 13 Votes
24 months ago

better throw away that 5k monitor/computer in 5 years when 5k finally becomes a standard.


Well in 5 years I'm sure many people will upgrade to the latest model of this machine anyway.

I guess Apple wants the Mac Pro users to get a 3rd party 4K display. Not a problem. Not everybody has to have an actual Apple display to use the Mac Pro.
Rating: 10 Votes
24 months ago

no 5k standalone soon?? well, why the **** not?!


Read the article.
Rating: 10 Votes
24 months ago

Well in 5 years I'm sure many people will upgrade to the latest model of this machine anyway.

I guess Apple wants the Mac Pro users to get a 3rd party 4K display. Not a problem. Not everybody has to have an actual Apple display to use the Mac Pro.


If they released a 5k display, only the Mac Pro would be able to output to it. Then they would have to advertise that it doesn't work with macbooks or the mac mini... it's a headache. Not worth it.
Rating: 8 Votes
24 months ago
I'm not going to say 'applefail' or 'if steve was still alive'.
But it just seems like Apple is pretty smug lately, flipping the finger to the people who buy their stuff on the regular.
You own a Mac Pro? Our most expensive item? Look elsewhere for a monitor for it, we can't be bothered.
But look at how thin our ipad is!
Rating: 8 Votes
24 months ago
It's been way too long...to keep waiting.:)
Rating: 7 Votes
24 months ago

I have a 15" rMBP for personal use and a 13" non-retina MBP for work, and I can't really tell the difference. I don't know if if I have bad eyesight, or just don't care. Meh.


Your eyesight must be very bad. I can't even look at non-retina macbook, it is so awful.

:apple:
Rating: 7 Votes
24 months ago


Despite a few missteps, they've executed an upgrade to most of their products very impressively over the past few months. The full realization of this will become apparent over the next few months, at which point I'm confident that they will issue an update for their Mac Pro, as well as possibly updated Thunderbolt displays. But I think part of the holdup for this is Intel releasing new processors and finishing the next version of Thunderbolt. Point your finger at Intel if you are looking for someone to blame for the rate of progress.


Well first of all, Marco is wrong -- TB3, if the leaked slide from Intel is accurate, will continue to use DP 1.2, not 1.3, but will have a bandwidth of 40Gbps. That's enough to run a single 5k display @ 60hz. That is supposedly slated for release next year.

But let's say that Apple won't release a new Cinema Display until 2016. Then they should have released a 4k display in the interim. To make Mac Pro customers wait an additional two years to have an Apple product to use as a display is not only shameful, but dilutes the halo power of the Mac Pro that they worked so hard to create when they reintroduced it last year as the top dog of the Mac lineup.

But it's not surprising. Apple has been sending mixed signals to professional users about their importance to the company for quite a few years now.
Rating: 6 Votes

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