OS X 10.10.3 Now Supports Dell's Dual-Cable 5K Monitor on Retina iMac and Mac Pro


macrumors bot
Original poster
Apr 12, 2001

With the release of OS X 10.10.3 last Wednesday, Apple has expanded support for high-resolution 4K and even 5K external displays (via 9to5Mac). Most notably, OS X 10.10.3 enables the Retina 5K iMac and 2013 Mac Pro to drive Dell's UP2715K 27-inch 5K display released late last year. The display requires more bandwidth than is currently supported over a current single DisplayPort/Thunderbolt cable, so it uses a dual-cable solution taking up two ports on the user's machine.

This bandwidth issue for the current DisplayPort standard has been seen as a major roadblock keeping Apple from releasing a standalone 5K Thunderbolt Display. With the Retina iMac, Apple has been able to build custom internal components to drive the massive display, but for external displays, a dual-cable solution such as that used by Dell has been considered by many to be "un-Apple like."

As a result, Apple has been widely expected to wait until the release of Intel's Skylake platform with DisplayPort 1.3 support later this year before releasing an external 5K Thunderbolt Display that will function over a single cable. Whether the inclusion of support for Dell's dual-cable solution in OS X 10.10.3 is a sign Apple may be willing to adopt that arrangement for its own display and perhaps release it earlier is, however, unclear.

Beyond 5K displays, OS X 10.10.3 has also expanded support for 4K displays to include "most single-stream 4K (3840x2160) displays" at 60 Hz, expanding beyond the previous support of only Multi-Stream Transport displays introduced in late updates to Mavericks. The new 4K display support will function with most of the Mac line, from the 27-inch iMac to the brand-new Retina MacBook. However, only the Mac Pro and iMac will support full 4096x2160 resolution at 60Hz.
With OS X Yosemite v10.10.3, most single-stream 4K (3840x2160) displays are supported at 60Hz operation on the following Mac computers:

- MacBook Pro (Retina, 13-inch, Early 2015)
- MacBook Pro (Retina, 15-inch, Mid 2014)
- Mac Pro (Late 2013)
- iMac (27-inch, Late 2013 and later)
- Mac mini (Late 2014)
- MacBook Air (Early 2015)
- MacBook (Retina, 12-inch, Early 2015)
As for the new 12-inch MacBook, the laptop will be able to support displays and rates of 3840x2160 at a 30 Hz refresh rate and 4096x2160 at a 24 Hz refresh rate. MacBook users wanting to use such a display will, of course, need to use Apple's USB-C Digital AV Multiport Adapter to do so.

Article Link: OS X 10.10.3 Now Supports Dell's Dual-Cable 5K Monitor on Retina iMac and Mac Pro


macrumors newbie
Feb 11, 2014
I can imagine their new standalone display to be as thin as an iPad and even with a similar design. Could also be available in the 3 colors. Would be sick and also a huge step forward for apple in the living room.


macrumors G3
Nov 26, 2007
Are we thinking the next MBP 15" will be Skylake or Broadwell? When are we expecting it... WWDC? Later this year?


Jan 8, 2013
Are we thinking the next MBP 15" will be Skylake or Broadwell? When are we expecting it... WWDC? Later this year?
Intel still updating broadwel and not a word about skylake..so if they update at wwdc it will be for sure broadwel


macrumors regular
Jul 21, 2014
Aurora, IL
I feel like support for my 3440 x 1440 Samsung SE790C display also improved on my MacBook Air 13" (Mid 2012) with 10.10.3. So far I am no longer seeing issues like I was on 10.10.2.


macrumors 604
Oct 17, 2014
I may never have the need or the room to run dual 5K displays on my desk, but it's good to know the option is there.

Are we thinking the next MBP 15" will be Skylake or Broadwell? When are we expecting it... WWDC? Later this year?
Skylake, perhaps later this year (fall at the soonest).


macrumors 68000
Jun 23, 2003
So. Cal.
Does OS X finally support dual monitors daisy chained through Displayport then? There are more people with that issue than own 5k monitors.

Seen lots of back and forth between Apple and Dell on this. If you boot a MacPro to Windows, you can daisy chain two Displayport monitors just fine. Boot to Mac OS X and it doesn't work.

Using two of my ports - one each for my monitors right now since I could never get it to work.


macrumors G5
May 2, 2002
I have Dell's identically-styled UP2414Q 4k display, which (at that 23.x-inch size) is a gorgeous sharp retina resolution, with a great-looking color gamut (as long as you don't use black/dark backgrounds or night scenes, which have a ton of lower-third glow.) OS X supports multiple scaled resolutions just like a retina MacBook Pro, and they all look great.

And aside from the picture, it's terrible! I wish there had been SOME other external retina display choice for my black Mac Pro. (But there wasn't: other 4k displays were too big, leaving pixels unsuitable for either 1:1 or scaled use.)

The problems are many, but chief among them:

- The built-in USB ports are unpowered (seriously!) and disconnect entirely from the computer when the display is asleep even if the computer is away. NEVER connect a USB stick or storage to the display.

- Cheaply made with some sheet-aluminum and some creaky plastic painted to not-really-match the aluminum. The portrait/landscape rotate (which I thought used to work but doesn't anymore) always sits at a slight angle off of level. You get used to it, but who wants an always-crooked monitor? Plus, a few tiny bits of dust and hair in between the layers of this brand-new display--like dead pixels but bigger. I could have asked for a warranty swap, but you get a refurb, which by all accounts is likely to be scuffed up and dirty and worse than the original.

- Awful controls. Trying to change the brightness is needless extra steps, with buttons that sometimes work and sometimes don't.

- No webcam, no speakers, no mic (so no iPhone handoff), no ambient light sensor (so you must fight those menus daily), no cleanable, dent-proof cover-glass, no MagSafe charger. This is NOT an Apple-level display, even if the panel itself is (mostly) nice.

- WORST OF ALL: it almost never wakes from sleep (and powering on/off) won't help. You basically have to power down your ENTIRE MAC every time you walk away, because otherwise you'll end up blind and having to force-shutdown. Which I've done many times, and yes, data loss can result. Only a full boot will make a picture appear reliably.

So... if you think a Dell is the display of your dreams, go in with low expectations. Expect a cheaply-made, unreliable stopgap until you can afford (and find!) something better.
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Oct 4, 2011
I don't like Dell. I just want a 4K Apple monitor for my 2013 Mac Pro.


macrumors 6502a
May 11, 2008
is everything!
and dell is still charging 2499 for just the monitor.. Apple should add support to use a second 5k imac as a monitor.. it's the same damn price..


macrumors 601
Dec 13, 2004
Why not the 15" with 750M too? With thunderbolt and hdmi, it should be enough bandwidth.


macrumors 68040
Jan 31, 2005
La Jolla, CA
Damn, I hope Apple releases at WWDC a 5K TB stand alone display. I am itching to get one for my MacPro.
Matte version please! :D


macrumors G5
May 2, 2002
I don't like Dell. I just want a 4K Apple monitor for my 2013 Mac Pro.
How I wish Apple would just slap the same panel as Dell's UP2414Q into a new Thunderbolt Display! Yes, it would be slightly smaller than the old (unavoidable for now) but I have mine scaled to extra workspace, and that's very workable.


macrumors G4
Jun 27, 2007
Central U.S.
I'd be happy with even "just" a Thunderbolt 2 4K display. But I'm waiting for Skylake anyway and by then won't personally need a new TB display if I'm going to get a 5K/8K/whateverK iMac. But I've wanted a new TB display for the past couple of years and Apple lost out on that sale.
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