Can I daisy-chain a DisplayPort monitor to the new Studio Display via Thunderbolt?

asasasaaaaaas wrote:

Thanks for the reply. From the sounds of it, it doesn't appear possible to run the SD2 (at 60Hz) and a second monitor from the MacBook Air at all?

You should be able to run both monitors from a

• M5 MacBook Air,
• M4 MacBook Air, or
• M3 MacBook Air that has the lid closed

(The M1 and M2 MacBook Airs only support one external display, and the Studio Display 2 has compatibility requirements that would keep it from working with any Intel-based MacBook Air.)

However, because of the bandwidth requirements of the Studio Display 2, you will need to connect your two monitors via different host ports. E.g.,

MacBook Air
    USB-C port 1 ------ Studio Display 2
    USB-C port 2 ------ [Optional] dock/hub ------ Dell S2727DS

The first connection would be a Thunderbolt one, whereas the second one might not involve Thunderbolt at all.

What Servant of Cats wrote is correct.

Your 2K display does not appear to fit in the bandwidth left over after the new Apple Studio Display is supplied with data. A dock will not make a difference, because there is not enough additional bandwidth on the Thunderbolt-4 cable to run a display like the one you described.

The only way it appears you could get a picture on a second external display is if it were a lower resolution, or a very low refresh rate.

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There is no requirement that you close the cover on your MacBook Air.to support external displays The built-in display can be used as a second display. On the 13-in model, that is just under 2K display, and just over 2K for the 15-in model. Both are HDR 10 bits/color displays natively.

My son used to use his laptop open on the desk in front of him and a larger external display up on a block of wood above. You could also place the MacBook Pro to the left or right with creative supports.

if you are doing work that requires more displays than that, a more capable machine (with more ports) would be appropriate.

asasasaaaaaas wrote:

Thanks. I'm looking to have the Studio Display 2 (non-XDR) as the main display connected to my MacBook Air. I'd like to run a USB-C/DisplayPort cable from the Dell S2725DS to the Studio Display, to extend my desktop across the two monitors. Hopefully this will be possible.

He's telling you that this is not possible. Even the new M5 MacBook Air only supports Thunderbolt 4. So the connection to the Studio Display 2 is going to use essentially all of the available bandwidth,

Would be frustrating to have to get a hub for this and not have the clean, single cable to Mac set-up.

Putting a hub between the MacBook Air and the Studio Display would not let you hook up your second display through that hub – even if we were talking about a Thunderbolt hub. At least not if we are talking about 60 Hz refresh rate for the Studio Display. If you could reduce the refresh rate to 30 Hz, and did so, that might free up bandwidth for running another display off the same Thunderbolt 3/4 host port, but most people probably would prefer not to do that.

asasasaaaaaas wrote:

Thanks for the reply. From the sounds of it, it doesn't appear possible to run the SD2 (at 60Hz) and a second monitor from the MacBook Air at all? Even if both monitors (and the MacBook) are connected to a thunderbolt hub? That just seems really odd.

I believe that Macs that support multiple monitors are willing to support up to two DisplayPort streams/sessions within a single Thunderbolt 3 or 4 connection.

If you are talking about 4K monitors, there's enough bandwidth for each of those two encapsulated DisplayPort sessions to drive a separate 4K @ 60 Hz monitor.

If you are talking about the 27" 5K Apple Studio Display 1, or the 32" 6K Apple Pro Display XDR, a connection to either one of those displays consumes both of the DisplayPort sessions available within the Thunderbolt 3 or 4 one. Each DisplayPort session carries the data necessary to refresh half of the 5K or 6K screen. So there is no spare DisplayPort session left over for a second monitor.

The Studio Display 2 supports Thunderbolt 5, which potentially has more bandwidth available for sending video than Thunderbolt 3 or 4. That increased bandwidth is why the Studio Display 2 permits daisy-chaining displays when it is connected to a computer that also supports Thunderbolt 5. MacBook Pros with M5 Pro and M5 Max chips are examples of such computers. MacBook Airs are not.

A single HDR 10 bits/color 5K display (like the new Apple Studio Display) uses essentially ALL of a ThunderBolt-3 or -4 port's bandwidth to get to 60 Hz refresh rate.

if using ThunderBolt-3 or -4, there is no bandwidth left over to support a second display of any description on the same cable out of the Mac..

The Dell S2725DS is a 27-inch QHD monitor with a resolution of 2560 x 1440 pixels, It features 8 bits/color and a refresh rate of 48 Hz to 100 Hz.

connectivity includes:

DisplayPort 1.2 which supports HBR2 at 17.28 GB/sec

Dual-Link DVI

Analog VGA

directly from a port on your Mac, that display can be supported with an ordinary USB-C adapter to DisplayPort, provided no single cable exceeds one meter in length.

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The specs for the new 27-in XDR display are somewhat ambiguous:

Connections:

Two Thunderbolt 5 ports (up to 120Gb/s) and two USB-C ports (up to 10Gb/s)

• One upstream Thunderbolt 5 port () for host (with 140W host charging)
• One downstream Thunderbolt 5 port () for connecting high-speed accessories or daisy-chaining additional displays
• Two USB-C ports (up to 10Gb/s) for connecting peripherals, storage, and networking

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As I read that spec, it is saying the display is willing to connect an additional Thunderbolt high speed accessory or additional genuine Thunderbolt Display.

It may not be willing to act as a Full ThunderBolt hub and provide a DisplayPort interface to an ordinary USB-C device or adapter on its Thunderbolt port.

So if the survival of your business depends on being able to do that display chaining, I suggest you not bet on it until that device is out in the wild and users can test it.

https://www.apple.com/studio-display-xdr/specs/

At the speeds (USB-3) display speeds you require, IF the USB-C ports will allow display data, that is all you need to support your additional display.

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What is fascinating about the old model '6K Apple Pro Display XDR' is that it uses up BOTH of the possible display connections all by itself:

The 6K Apple Pro Display XDR, which macOS allows to connect using two HBR3 connections to a Mac, doesn't support Display Stream Compression (DSC). That would be 51.84 Gbit/s, impossible for Thunderbolt 3, but it works because the two 3008×3384 10bpc 60 Hz 648.91 MHz signals of the XDR display only require 38.9 Gbit/s total and Thunderbolt does not transmit the DisplayPort stuffing symbols used to fill the HBR3 bandwidth.

https://en.wikipedia.org/wiki/Thunderbolt_(interface)

Note that while Apple says that the new Studio Display is compatible with the M4 MacBook Air, that MacBook Air does not support Thunderbolt 5.

This means that the connection between the M4 MacBook Air and the new Studio Display will not be able to take advantage of Thunderbolt 5's ability to allocate up to 120 Gb/s for display data. It will be limited to Thunderbolt 4 speeds. Perhaps that will be enough, but if you're looking at whether daisy-chaining works with that display and other Macs, the configurations of interest would be those where those other Macs also have "just" Thunderbolt 4.