Can you daisy chain two 4K monitors with USB-C ports to a 14" MacBook Pro, M1 Chip computer?

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Can you daisy chain two 4K monitors with USB-C ports to a 14" MacBook Pro, M1 Chip computer?

I have ordered the new 14" MacBook Pro with the M1 Pro chip. I am looking for one external display now and want to future proof my selection in case I want to get a 2nd display in the future. I am also looking for a display that supports a photography workflow (hobbyist) so I am looking for one that covers the Adobe RGB space. It turns out that currently these monitors in a somewhat affordable range have a USB-C connection at best. Thunderbolt displays don't appear to have good coverage of the Adobe RGB space at present.

So, if I get a display that has a USB-C (not a Thunderbolt) port than what are the specs of computer displays that I could daisy chain? If I cannot daisy chain two 4K monitors than what are the other work-arounds? I know I could use 2 of the three T4/USB-4 laptop ports? Could you hook up two monitors with a dock?

Any information will be helpful.

I will get my laptop in early December (trading in 27" 5K iMac)

Thanks.

Posted on Nov 7, 2021 4:13 PM

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Answer 1

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Joe_Appleseed

Level 1

8 points

Nov 27, 2021 12:11 PM in response to minimejh

To be more clear what Grant Bennet-Alder wrote:

you need a Thunderbolt 3 cable specified with 40 Gbit/s from your laptop to the first display or dock (wherever the connection to the second displays comes from) to get it working.

Some suppliers (e.g. Samsung) claim to provide a Thunderbolt 3 cable with their displays, but this eventually may be only a passive one, capable to transfer only 20 Gbit/s.

So this will not work!

Sadly they don't specify the performance in their data sheets.

I wondered why Daisy Chain did not work with my MBPro (2016) and my two 4K Samsung Displays over the cables that came along with them.

Even the support (in this case Samsung) couldn't tell how the supplied cable is exactly specified.

In the manual it's written that for Daisy Chain a cable with 40 Gbit/s is needed and to be purchased separately.

So I recommend to check documentation for your gear first, not only specification given on websites or data sheets.

With the Apple Thunderbolt 3 cable (0.8m) now it works well :)

HInt:

you can check the performance on your ports via the system report (-> Thunderbolt).

Empty ports are shown with 40 Gbit/s.

If you have connected a device it shows the performance available.

In my case with the supplied Samsung cables it was only 20 Gbit/s.

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Answer 2

Nov 7, 2021 4:42 PM in response to minimejh

Yes, with M1 Max & M1 Pro: Connect a display to your Mac - Apple Support

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Answer 3

Nov 7, 2021 5:05 PM in response to minimejh

An important point is that the connection to the first display of a daisy-chain MUST use a connection with TWO data pathways in it, such as Thunderbolt. The chain on to the second can generally use whatever you please, provided the first display support it.

You can not, for example, daisy-chain from the computer using only HDMI, because it is already full at one display's worth of data, and has no additional pathway for the second display's data.

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Answer 4

BobHarris

Level 9

55,049 points

Nov 7, 2021 6:58 PM in response to minimejh

Thunderbolt 4 can be daisy chained (it can even be hubbed), but a USB-C that is NOT Thunderbolt is going to be using the DisplayPort over USB protocols. As far as I know, DisplayPort over USB protocol only supports a single DisplayPort device from that Mac port.

You can of course use a 2nd Thunderbolt 4 port on the Mac to drive a 2nd monitor.

Or you can get a Thunderbolt 3 (or 4) dock that supports 2 monitors. With some shopping you can find a dock that supports the display ports you prefer.

You also have the option of using DisplayLink software and something like a StarTech USB-to-HDMI adapter or USB-to-DisplayPort adapter to get more than 2 external monitors. This will not be as high performance, but if what you need is screen real estate for controls, web browser, email etc... these monitors would work for that.

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