Daisy chain two display port monitors (Dell U2913WM) to new Mac mini Thunderbolt?

I used to build my own Windows systems since the late 90’s. About three years ago I saw the value in the mobility of a laptop so I bought a Dell Precision. That thing was so heavy and had so many overheating issues and audio driver issues that I finally decided to try my luck with Apple and their new Thunderbolt 2 equipped Macbook Pro last October.

What I’m starting to observe (and other Mac users have probably known this all along) is that Apple is not in the business of making its machines compatible with third-party hardware. If the third-party wants to manufacture their hardware to Apple’s specs — fine. Otherwise, Apple is not going to invest any effort into designing for compatibility because they already make hardware that is compatible with their machines.

What is so frustrating to me is that Apple only has to implement a concrete specification for a hardware standard: DisplayPort 1.2 and they’re not even doing that. And yes, as others have pointed out it is an OS issue because you can daisy chain two DisplayPort 1.2 Dell’s just fine if you’re running Windows on Mac hardware.

But DisplayPort 1.2 support isn’t the only issue with Apple’s lackluster OS when it comes to these new Dell monitors. Mavericks sees these monitors as televisions and as a result sends a YPbPr signal instead of RGB. If you do a Google search for “osx dell monitor” you’ll see on the first page “Blurry text on Dell Monitor + Mac OS X” and “Force RGB mode in Mac OS X” among other results that all describe how to run a Ruby script that forces OS X to recognize these monitors as monitors. I had to run the script for my two U3014’s. And no, the scripts didn’t fix the daisy chain issue. 🙂

So like everyone else with a new MBP and non-Apple monitors, I’m stuck using both Thunderbolt ports as DisplayPorts if I want full resolution on both monitors. And I’m stuck having to run a script every time there is a Mavericks OS update just so that the ****** OS will send an RGB signal to my monitors.

It makes me feel like an idiot for spending so much on what would otherwise be the perfect system — much to the schadenfreude of Windows and Linux fanboys. Honestly, if Apple could just figure out this one little thing I’ll still take it over Windows 8 or Ubuntu + Unity any day.

Finally, allow me to drive a nail through any shred of hope lest anyone be still holding out for Dell monitor support from Apple: http://en.community.dell.com/support-forums/peripherals/f/3529/t/19347208.aspx

The first line from that page sets the stage for all of the Dell-Apple monitor issues outlined thereafter: "We do not validate our monitors with any apple proprietary hardware or software."

*sigh*

Guess the best place for these monitors now is eBay. And goody -- I get to wait like every other Mac owner for Apple to release a Thunderbolt Display that offers my current Dell's resolution or better (2560x1600). Oh and I'll get to pay a premium for it too! Thanks Apple! I thought freedom of choice and compitition were good things for me as a consumer but that was really stupid of me -- obviously a complete lack of choice and sumbission to your exclusive product specs and timelines are the best thing for all of us! More Cool-Aid please!

😠

Thanks for the info on RGB and YPbPr signals, .monger. No doubt I would have been sorely dissapointed at finding this out after buying one.

I've worked with a 2010 MacPro for the last 2 years, connected to an Eizo Flexscan 24" (can't remember the exact model right now), and the image quality is fine. It's a work machine, maintained by an IT department at a publishing company, and it's still running 10.6.8. The display is connected using DVI from an ATI 5770. Why doesn't this have any problem outputting correctly? Or, more to the point, why does the 2013 MBPr have a problem with monitors from other manufacturers.

I would guess that Apple have purposefully written it in to the OS that the GPU should output YPbPr singals in order to push people towards their own brand of displays. What I mean to say is that it is not a mistake by Apple, it is intentional. If Snow Leopard could put out an accurate signal back in 2009, surely Mavericks is capable in 2014.

I would happily buy Apple displays, however, the problem is that Apple's displays are over priced, and under specked - I don't care how pretty they are. They can't do what the Dells can do.

It would seem that no matter what Apple system you're using, if you have invested in an Apple product in 2014, and you want to use that system for professional work, you're going to be stuck behind your peers working on Windows systems. That's a shame because Apple used to make machines that were design to let you be creative, using cutting edge technology, on stable platforms. That just isn't true anymore.

Well stated. I agree

Just got two new Dell U2414H monitors. Both are Displayport 1.2. I cannot get them to daisy chain on a nMP. They work great plugged in to separate ports. The only thread I have come across that clarifys the issue points to the fact that a Mac running Windows will daisy chain montitors that support it. Which then leads to the conclusion, the hardware definitely supports daisy chaining, it's OSX Mavericks 10.9.2 (I run this and it still doesn't work) that doesn't yet support it.

Displayport 1.2

https://discussions.apple.com/thread/5496129?answerId=23655430022#23655430022

From the Discussion.....

Cheule

Re: Displayport 1.2

Feb 19, 2014 8:48 PM ( in response to Bagellord)

Bagellord, I have a brand new Mac Pro (late 2013, cylinder) and Mavericks 10.9.1. The OS does not support DisplayPort 1.2. I have a DP 1.2 monitor (LG 29" Ultrawide), and the monitor functions properly while set to DP 1.2 mode under Windows 8.1, but not under Mavericks. So that indicates to me that the hardware (Mac Pro) and Windows 8.1 support it, but 10.9.1 does not. Shame.

Mavericks 10.9.3 is now out and is supposed to amongst other things improve support for 4K video which in turn implies better support for Displayport 1.2

Have you tried 10.9.3 with daisy-chaining your monitors?

I haven't had a chance yet. Possibly over the weekend I'll give it a try. Fingers crossed!

Yeah I was curious as well after applying the update this morning.

Unfortunately, the daisy-chain behavior is the exact same as before -- mirroring with no option to tell the OS to treat the monitors as separate.

😟

I'm resigned to believing this feature isn't now, nor will ever be on Apple's radar. I'm resigned to believing that the only solution to my two-thunderbolt-ports-monopolized-by-my-two-monitors problem is the Sonnet Echo 15... once they release it with Thunderbolt 2 support -- which will be never but that will still be sooner than Apple providing DisplyPort 1.2 daisy-chain support.

*sigh*

Before i bought my MBP last October, a friend and Mac user warned me that Apple doesn't like supporting third-party hardware. I thought he was exaggerating, given how successful Apple has been as a company. Turns out he really wasn't exaggerating.

If as per posts by other users a new Mac Pro supports DisplayPort daisy-chaining under Windows 8.1 via Boot Camp but the same new Mac Pro and monitors do not work under Mavericks then clearly this is not a hardware issue.

I have not been able to find definitive evidence, but if Apple have signed up to be officially certified or complaint with the Displayport specification then it could be argued they are in breach of the specification since daisy-chaining aka. multi-stream transport (MST) is part of the Displayport 1.2 specification.

Note: Mini Displayport is part of the Displayport 1.2 specification and 4K display support requires Displayport 1.2. As Apple do support 4K displays clearly they are using Displayport 1.2 which is known to be supported by Apple's hardware as proven in Windows and by the fact that the manufacturer specifications for the video chips used by Apple list this which again is proved by the fact it works in Windows using the same hardware.

What is even more puzzling is that according to this article http://www.anandtech.com/show/7603/mac-pro-review-late-2013/11 support for 4K displays is achieved by using MST to send two streams to a single 4K display in order to support the extra number of pixels.

So it appears Apple are supporting MST with their own Mini Displayport and Thunderbolt displays, and are also supporting it with third-party 4K displays, but apparently are deliberately blocking it with other Displayport displays.

This if true is outrageous behavior on Apple's part. Perhaps we should send complaints to the Displayport organisation. See http://www.vesa.org/displayport-developer/compliance/ (there are some email contacts listed)

The original thread asks about daisy-chaining two Dell monitors via Displayport on the current Mac mini. As far as I can see this is not possible not only because people are posting here with problems trying to do it, but due to the specifications of the current Mac mini (2012).

The current Mac mini has an Intel HD 4000 video chip, this video chip uses Displayport 1.1a and Displayport 1.1a does not support a function called MST. MST stands for Multi Stream Transport and lets you send multiple video streams over a single cable, in this can one would be used per screen.

See this page for Intel's official description of their video chip capabilities which shows the HD 4000 only does Displayport 1.1

https://software.intel.com/en-us/articles/quick-reference-guide-to-intel-process or-graphics

The new Mac Pro and Retina MacBook Pro, both support Displayport 1.2 and both support MST. In fact MST is also used to drive a 4K display at 60fps, a single stream can only do a 4K display at 30fps so to get 60fps two streams are used. In theory therefore the new Mac Pro and Retina MacBook Pro should be able to do daisy-chaining with Dell screens. I have seen posts suggesting this does indeed work on these Macs in Windows8 but apparently not in OS X.

I can confirm that daisy chaining DP monitors does not work on a Late 2013 maxed out rMBP. All it will do is mirror the display that is connected to the computer. I got apple to verify it does not work. Their reason was it had to do with the graphics switching and the power needed for the displays. I have even tried 10.10 in hopes that they would come to their senses.. No luck... Please make this work Apple!!!! We are very limited on ports as it is we shouldn't have to either buy thunderbolt displays or not be able to run more than two displays just to be able to have Ethernet.

Well people have said it DOES in fact work - with Windows on a Mac. So what's up with that? It's an OSX issue if that is the case.

It is absolutely an OS X problem, all they have to do is stop blocking it in their proprietary set of drivers. I can mirror all day long in OS X. It is a complete dick move. There has got to be some mid level work around for this. Come on, if windows can do it easily on crap hardware but with a graphics card that supports 1.2 then my $2800 piece of awesomeness should be able to handle it fine without degrading the os.

I have a Mac mini (late 2012) and I hope to use dual monitor system of two dell U2713H.

My boss has already promised that he will buy them for me.

However, I was very disappointed after reading this threads.

The current Mac mini has an Intel HD 4000 video chip, this video chip uses Displayport 1.1a and Displayport 1.1a does not support a function called MST. MST stands for Multi Stream Transport and lets you send multiple video streams over a single cable, in this can one would be used per screen.

See this page for Intel's official description of their video chip capabilities which shows the HD 4000 only does Displayport 1.1

https://software.intel.com/en-us/articles/quick-reference-guide-to-intel-process or-graphics

I've read the article, so I've given up daisy-chaining.

However, how about USB-DisplayPort connecting?

For example, http://www.tripplite.com/usb-3.0-superspeed-to-displayport-dual-monitor-external -video-graphics-card%20adapter-512-mb-sdram-2560x1600-1080p~U344001DP/

One monitor uses mini-displayport(thunderbolt), and the other uses usb port with this adapter.

Is there anyone who tests this way?

If so, could you please share the information?

Thank you. 🙂

Yes it will work if the monitor is less that

Supports video resolutions up to 2560 x 1600 @ 60Hz