Apple HD Cinema Display 30

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Level 1

14 points

Apple HD Cinema Display 30

OK, I am enountering a very odd problem.

I have a 30" Cinema HD Display that connects to a Mac via an Apple Dual DVI adapter which has Thunderbolt 2 and USB. (It needs both connections.)

1) This display functions perfectly with a 2015 MacBook Pro. (No adapters needed).

2) This display functions perfectly with a 2018 Mac mini, using an Apple Thunderbolt C - Thunderbolt 2 adapter. USB connects directly to the computer.

3) To Connect to the MacBook Pro 2021, in addition to an Apple Thunderbolt C - Thunderbolt 2 adapter for video, it also needs a USB-C to USB A adapter, which I am using an Apple Branded one. However, the 2021 MacBook Pro, in the Display preferences, I can not see an 2nd monitor and doesn't show Arrangement tabs.

Any suggestions?

Posted on Dec 18, 2021 1:08 PM

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Answer 1

Best reply

Grant Bennet-Alder

Level 10

127,249 points

Dec 18, 2021 2:51 PM in response to Doug Weiner

The Apple Dual-Link DVI adapter features a Mini DisplayPort (not ThunderBolt) input. The adapter requires a source of 5 Volt power on its USB port, to run its internal electronics. The display does not require a "live" USB-A connection unless you want to have the brightness slider in the Mac's Displays control panel or use the USB Hub in the displays. An iPad charger will suffice to provide that USB 5 Volt power.

For your 2018 Mac mini setup, I do not understand how that is working. Apple's ThunderBolt-3 <-> ThunderBolt-2 adapter claims to support ONLY Thunderbolt displays.

_________

If you were to ask me in isolation how to hook this up, I would tell you it requires a USB-C to Mini DisplayPort adapter for video, the Apple Dual-Link DVI adapter you were using, and a source of 5 Volt power to run the Dual-Link DVI adapter.

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Answer 2

Jan 4, 2022 11:36 AM in response to Doug Weiner

This diagram (lifted from Wikipedia) showing the signals helps me understand:

(drag and drop on Preview to see larger)

Single-Link DVI is good for displays up to 1920 wide. It can have the center six pins (medium blue in the diagram) de-populated. Single-Link DVI cables do not connect the center six conductors end-to-end, whether they have the pins or not.

To go wider than 1920 wide, you need more data. The single-link DVI is already switching pretty fast, so they opted to add another three signals (six conductors) to supply the additional information. This makes converting Dual-Link DVI to and from anything else a nightmare.

Both HDMI and DisplayPort opted instead to try to switch the signals faster on the same number of conductors, which is ultimately easier to convert.

--------

The other wonky thing about the DVI connector is that the computer port supplies a VGA signal DIRECTLY -- in the blade at one end, the four pins around it, and one more Sync from the top row of the grid salmon-pink on the diagram). to get VGA, one uses a thing that should be called an Extractor rather than a Converter.

You can also see illustrated that once you plug in an "ordinary" DVI cable, the VGA signals will be left unconnected, and un-available at the other end of the DVI cable. This illustrates why it is generally essential to make the adaptation in at most ONE adapter -- because the wealth of options may only be available directly on the computer port, not at the far end of a connected cable.

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Answer 3

Doug Weiner Author

Level 1

14 points

Dec 18, 2021 3:48 PM in response to Grant Bennet-Alder

Grant, thanks! Your explanation is extremely useful.... and......

You pointed out something I have mis-remembered. On the Mac Mini setup I have a 3rd party USBC adapter that connects to the monitor dual link cable. It was so long ago I created the mini set-up and because the 2015 MacBook Pro had Thunderbolt 2 ports, I just assumed (falsely remembered) that adapter on the Mini was also a Thunderbolt 3 --> 2 adapter. Based on your explanation, it must actually be a USB-C -> Mini display port adapter. All my computers are in different places so I can not swap out parts right now, but I just ordered a new USBC-> display port adapter from Amazon and it will be here tomorrow, and I will report back.

Again Thanks.

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Answer 4

zookeep

Level 1

18 points

Jan 4, 2022 8:14 AM in response to Grant Bennet-Alder

Hi Grant,

Apologies if I need to initiate a new thread, happy to learn how to do so. In short: I have a 2002 Cinema HD Display, an Apple DVI to ADC adapter, both currently working perfectly with a 2008 Mac Pro. I would like to use this display with a 2019 Macbook Pro with USB-C ports. I'm not terribly technical and would appreciate any guidance. Thanks!

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Answer 5

Doug Weiner Author

Level 1

14 points

Jan 4, 2022 8:34 AM in response to zookeep

There are a few different sizes of Apple monitors with the 30” requiring one special adapter.

Here is what you need for the 30”.

From Computer:

1) USB c to mini Display port adapter.

1a) You will need a USB-a port as well for additional power. So either a power supply with USB port or a usb-c to usb-a adapter.

2) Dual DVI to display port adapter. (The best is an Apple one but are available usually on eBay.) Key here is Dual DVI. 30” Apple monitor requires this special adapter. Smaller Apple displays (lower resolution) and more modern large hi-res monitors do not need this adapter.

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Answer 6

Doug Weiner Author

Level 1

14 points

Jan 4, 2022 9:04 AM in response to zookeep

This cable:

USB Type C to Mini DisplayPort... https://www.amazon.com/dp/B0836HGBD7?ref=ppx_pop_mob_ap_share

and this cable:

Mini DisplayPort to DVI, Benfei Gold-Plated Mini DP to DVI (Thunderbolt Compatible) Male to Female Adapter Compatible with MacBook Air/Pro, Microsoft Surface Pro/Dock, Monitor, Projector and More https://www.amazon.com/dp/B0796C2QC8/ref=cm_sw_r_cp_api_glt_fabc_5R9M3XYXC5G7KAV0ABRM?_encoding=UTF8&psc=1

should work. Try these and cbs be returned from Amazon if they don’t .

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Answer 7

Jan 4, 2022 9:11 AM in response to zookeep

No, there is another problem. You generally can not "stack" adapters. You must make the transition from computer output to display input in at most ONE adapter.

so you need A USB-C to (Single-Link, good for up to 1920 wide) DVI adapter. This one provides an additional USB-C charge-only port:

Monoprice Select Series USB-C to DVI and USB-C (F) Dual Port Adapter - Product # 15243 - $18.99

For a few dollars more you can have a USB-A shipped USB-3 port as well:

Monoprice Select Series USB-C to DVI, USB-C, USB Type-A Multiport Adapter - Product # 15759 - $28.99

EDIT: The Amazon ones posted above will likely do the job as well.

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Answer 8

Doug Weiner Author

Level 1

14 points

Jan 4, 2022 10:48 AM in response to Grant Bennet-Alder

Grant,

Just an FYI. I do stack both the USB-C to display port to an Apple Branded dual DVI port adapter (I even run a nice mono price 15 foot long dvi cable between the two with no problem.

But Grant it right, with using third party adapters, they can get a little finicky. You just have to experiment.

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Answer 9

Jan 4, 2022 10:52 AM in response to Doug Weiner

The Apple Mini DisplayPort to Dual-Link DVI adapter is unlike any other, in its ability to be stacked with a mini DisplayPort adapter form the computer. That adapter is also unique in that it requires substantial external power, which means its USB-A pigtail MUST be plugged into something that can provide that power (which can be something like an iPad charger instead of a USB port).

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Answer 10

Doug Weiner Author

Level 1

14 points

Jan 4, 2022 11:19 AM in response to zookeep

FYI... this is only going to confuse matters...

First Understanding the basic problem:

From my understanding, basically the DVI specification can't carry more than 1920 wide or like 1200 tall at more that 30Hz (refresh rate.) Please do not quote me on the numbers above, but understand DVI can only deliver a certain amount of Data based on the general function of = height * width * refresh rate.

The older 30" Apple HD monitors can deliver a lot more data than what a single DVI can deliver so Apple used a technology called "Dual DVI," and even more confusing is that there are a couple of flavors of "Dual DVI" and Apple's version was only used by them. Basically Dual DVI delivers the signal in 2 parts and then re-syncs at the monitor.). This unique Apple Dual DVI flavor makes buying the correct dual DVI adapter tricky on Amazon. Good news is for Apple HD monitors under 30" (27" and 24"), they don't use that much data, so don't need the dual DVI.... I think. So for a 23", I recommend skipping the extra headache and get the single DVI solution.

What to watch for when buying dual DVI.

The Dual version you listed from Amazon.... there are two flavors of that one and honestly I am not clear exactly which one works because the tiles say one thing but the reviews and fine details say otherwise.

This one in the title says it doesn't work with the 30" but review comments say it does.

https://www.amazon.com/dp/B07QKM856C?psc=1&ref=ppx_pop_dt_b_product_details

and this one:

https://www.amazon.com/dp/B08B7FSVTL?psc=1&ref=ppx_yo2_dt_b_product_details

This is why I just spend the extra dollars and look on e-bay for the Apple Branded dual DVI. I had an off brand years ago and it worked... most of the time. Just tired of 'most of the time'.

NOTE:

Also Grant makes a fine point, with the Apple branded Dual DVI part, you need to plug the USB pigtail into USB power. With the amazon one, you do not.

Back to a simpler solution,

Get the cheaper single DVI solution from Amazon. Stack it on top of the USB-C to display port adapter and should work just fine. But buy them all (The ones above) and return the ones you don't use.

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Answer 11

zookeep

Level 1

18 points

Jan 4, 2022 8:53 AM in response to Doug Weiner

Ok. Is the "mini display port" something other than the USB-C port on the Macbook Pro? I do understand the "female DVI cable". Sorry for the painfully fundamental questions.

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