Two computers and one Studio Display?

[diatomaceousErf]

Decided to try one of the USB-C switches. CableDeconn type.

Seemingly works fine with their included cables attached to it - then to my MacBook or Mac Studio... of course it is showing the lower Thunderbolt rate of 20 gb/s or whatever.

Question - what if any, are the disadvantages to running studio display at this lower rate? Sorry if this has been asked already - couldn't find a definitive answer.

Thanks.

 

[jabbr]

probably just limited bandwidth for the usb-c ports on the back

 

[joevt]

Seemingly works fine with their included cables attached to it - then to my MacBook or Mac Studio... of course it is showing the lower Thunderbolt rate of 20 gb/s or whatever.

Question - what if any, are the disadvantages to running studio display at this lower rate? Sorry if this has been asked already - couldn't find a definitive answer.

Only the write speed would be significantly reduced since DisplayPort is mostly one way and Thunderbolt has separate wires for transmit and receive.

With DSC and a Thunderbolt 20 Gb/s connection, the Apple Studio Display uses ≈ 11.232 Gbps (936MHz x 12bpp) leaving 8.768 Gbps for USB writes.

With DSC and a Thunderbolt 20 Gb/s connection, the Apple Pro Display XDR uses ≈ 15.432 Gbps (1286MHz x 12bpp) leaving 4.568 Gbps for USB writes.

With a Thunderbolt 20 Gb/s connection and no DSC, the displays would be limited to 4K60 which is 16 Gbps (533MHz x 30bpp) leaving only 4 Gbps for USB writes or 12.8 Gbps (533MHz x 24bpp) leaving only 7.2 Gbps for USB writes.

If the displays are connected as USB instead of Thunderbolt, then USB read/write would be limited to USB 2.0 speed of 480 Mb/s.

 

[diatomaceousErf]

Only the write speed would be significantly reduced since DisplayPort is mostly one way and Thunderbolt has separate wires for transmit and receive.

With DSC and a Thunderbolt 20 Gb/s connection, the Apple Studio Display uses ≈ 11.232 Gbps (936MHz x 12bpp) leaving 8.768 Gbps for USB writes.

With DSC and a Thunderbolt 20 Gb/s connection, the Apple Pro Display XDR uses ≈ 15.432 Gbps (1286MHz x 12bpp) leaving 4.568 Gbps for USB writes.

With a Thunderbolt 20 Gb/s connection and no DSC, the displays would be limited to 4K60 which is 16 Gbps (533MHz x 30bpp) leaving only 4 Gbps for USB writes or 12.8 Gbps (533MHz x 24bpp) leaving only 7.2 Gbps for USB writes.

If the displays are connected as USB instead of Thunderbolt, then USB read/write would be limited to USB 2.0 speed of 480 Mb/s.

Would this (DSC) affect the quality of the camera, mics, or speaker sound though?

 

[joevt]

Would this (DSC) affect the quality of the camera, mics, or speaker sound though?

Someone with a Studio Display can tell us if those devices are USB 2.0, 3.0, or 3.1 gen 2.

 

[diatomaceousErf]

Someone with a Studio Display can tell us if those devices are USB 2.0, 3.0, or 3.1 gen 2.

Not certain where to check that specifically. It just says `USB` next to speakers and mic in the system info - `Sample rate 48000`. I can see if the rate changes with the switch plugged back in...

Can't find anything similar about the built in camera.

 

[joevt]

Not certain where to check that specifically. It just says `USB` next to speakers and mic in the system info - `Sample rate 48000`. I can see if the rate changes with the switch plugged back in...

Can't find anything similar about the built in camera.

System Information.app
In Monterey: Apple menu -> About This Mac -> System Report... -> USB. Then find the USB Bus that corresponds to the display. Each USB device will say what speed they are connected at.
USB 2.0: Speed: Up to 480 Mb/s
USB 3.0: Speed: Up to 5 Gb/s
USB 3.1 gen 2:Speed: Up to 10 Gb/s

 

[diatomaceousErf]

sorry for the delayed response.

so for both connection types Studio Display device appears on USB 3.1 Bus - under 'USB2 Hub' -> with speed `Speed: Up to 480 Mb/s`

 

[joevt]

sorry for the delayed response.

so for both connection types Studio Display device appears on USB 3.1 Bus - under 'USB2 Hub' -> with speed `Speed: Up to 480 Mb/s`

There are multiple devices. Provide output from this command:
system_profiler SPUSBDataType

 

[diatomaceousErf]

Usb-c switch -

USB:



USB 3.1 Bus:



Host Controller Driver: AppleT6000USBXHCI



USB 3.1 Bus:



Host Controller Driver: AppleT6000USBXHCI



USB 3.1 Bus:



Host Controller Driver: AppleT6000USBXHCI



USB 3.1 Bus:



Host Controller Driver: AppleT6000USBXHCI



USB 3.1 Bus:



Host Controller Driver: AppleEmbeddedUSBXHCIASMedia3142

PCI Device ID:

PCI Revision ID: 0x0000

PCI Vendor ID: 0x1b21



USB2 Hub:



Product ID:

Vendor ID: 0x05ac (Apple Inc.)

Version: 53.07

Serial Number:

Speed: Up to 480 Mb/s

Manufacturer: Apple

Location ID:

Current Available (mA): 500

Current Required (mA): 0

Extra Operating Current (mA): 0

Built-In: Yes



USB3 Gen2 Hub:



Product ID:

Vendor ID: 0x05ac (Apple Inc.)

Version: 53.07

Serial Number:

Speed: Up to 10 Gb/s

Manufacturer: Apple

Location ID:

Current Available (mA): 900

Current Required (mA): 0

Extra Operating Current (mA): 0

Built-In: Yes



USB 3.1 Bus:



Host Controller Driver: AppleUSBXHCITR

PCI Device ID:

PCI Revision ID: 0x0006

PCI Vendor ID: 0x8086



USB3 Gen2 Hub:



Product ID:

Vendor ID: 0x05ac (Apple Inc.)

Version: 52.12

Serial Number:

Speed: Up to 10 Gb/s

Manufacturer: Apple

Location ID:

Current Available (mA): 900

Current Required (mA): 0

Extra Operating Current (mA): 0



USB2 Hub:



Product ID:

Vendor ID: 0x05ac (Apple Inc.)

Version: 52.12

Serial Number:

Speed: Up to 480 Mb/s

Manufacturer: Apple

Location ID:

Current Available (mA): 500

Current Required (mA): 0

Extra Operating Current (mA): 0



Studio Display:



Product ID:

Vendor ID: 0x05ac (Apple Inc.)

Version: 2.01

Serial Number:

Speed: Up to 480 Mb/s

Manufacturer: Apple Inc.

Location ID:

Current Available (mA): 500

Current Required (mA): 500

Extra Operating Current (mA): 0



Thunderbolt cable -

USB:



USB 3.1 Bus:



Host Controller Driver: AppleT6000USBXHCI



USB 3.1 Bus:



Host Controller Driver: AppleT6000USBXHCI



USB 3.1 Bus:



Host Controller Driver: AppleT6000USBXHCI



USB 3.1 Bus:



Host Controller Driver: AppleT6000USBXHCI



USB 3.1 Bus:



Host Controller Driver: AppleEmbeddedUSBXHCIASMedia3142

PCI Device ID:

PCI Revision ID: 0x0000

PCI Vendor ID: 0x1b21



USB2 Hub:



Product ID:

Vendor ID: 0x05ac (Apple Inc.)

Version: 53.07

Serial Number:

Speed: Up to 480 Mb/s

Manufacturer: Apple

Location ID:

Current Available (mA): 500

Current Required (mA): 0

Extra Operating Current (mA): 0

Built-In: Yes



USB3 Gen2 Hub:



Product ID:

Vendor ID: 0x05ac (Apple Inc.)

Version: 53.07

Serial Number:

Speed: Up to 10 Gb/s

Manufacturer: Apple

Location ID:

Current Available (mA): 900

Current Required (mA): 0

Extra Operating Current (mA): 0

Built-In: Yes



USB 3.1 Bus:



Host Controller Driver: AppleUSBXHCITR

PCI Device ID:

PCI Revision ID: 0x0006

PCI Vendor ID: 0x8086



USB3 Gen2 Hub:



Product ID:

Vendor ID: 0x05ac (Apple Inc.)

Version: 52.12

Serial Number:

Speed: Up to 10 Gb/s

Manufacturer: Apple

Location ID:

Current Available (mA): 900

Current Required (mA): 0

Extra Operating Current (mA): 0



USB2 Hub:



Product ID:

Vendor ID: 0x05ac (Apple Inc.)

Version: 52.12

Serial Number:

Speed: Up to 480 Mb/s

Manufacturer: Apple

Location ID:

Current Available (mA): 500

Current Required (mA): 0

Extra Operating Current (mA): 0



Studio Display:



Product ID:

Vendor ID: 0x05ac (Apple Inc.)

Version: 2.01

Serial Number:

Speed: Up to 480 Mb/s

Manufacturer: Apple Inc.

Location ID:

Current Available (mA): 500

Current Required (mA): 500

Extra Operating Current (mA): 0

 

[joevt]

Usb-c switch -

Why did you remove the product ID and device ID's? They are not unique identifiers. If you took the time to do that, then you could have taken the time to notice that both the USB-C switch and Thunderbolt cable have the exact same output and to remove the extra spaces (use a text editor when copying from Terminal.app - I don't know why copying from Terminal.app to Safari adds all those blank lines). Also, when pasting text from source code or Terminal output, it's useful to surround the text with [code] and [/code] to preserve monospace formatting.

Anyway, regarding the output, I only see one USB device connected to the Apple Studio Display - everything else is just hubs. I don't know what device it is since the Product ID is missing. I don't see a camera device or audio device. Maybe provide the entire output of system_profiler SPUSBDataType so it can be interpreted properly.

 

[diatomaceousErf]

Sure.

That is the whole output. I just removed some IDs cause you can never be too careful.

All we are trying to determine is whether the bandwidth for the built-in devices (FaceTime cam, speakers, mics) is the same in each scenario. When running the command everything shows up in the same order and each with the same speed / specs - so I am not sure why a product ID is pertinent if all you care about is any change in the connection type / bandwidth.

 

[joevt]

Sure.

That is the whole output. I just removed some IDs cause you can never be too careful.

All we are trying to determine is whether the bandwidth for the built-in devices (FaceTime cam, speakers, mics) is the same in each scenario. When running the command everything shows up in the same order and each with the same speed / specs - so I am not sure why a product ID is pertinent if all you care about is any change in the connection type / bandwidth.

Where's the camera and audio device? Do they work? Are they not USB devices? Are they in the PCI list?

I was going to check if the device id's exist in the USB database https://usb-ids.gowdy.us/read/UD/05ac which is used by the lsusb.py command in linux. lsusb.py doesn't work in macOS but lsusb does (both from brew install usbutils). lsusb uses udev hwdb.bin but I don't know how to install that in macOS or if the macOS version of lsusb would use it. I think hwdb is built from usb.ids for USB devices at least, so maybe the thing to do is create a udev hwdb library that just reads the data from usb.ids....

 

[thedon1]

I've got some bad news to report for anyone considering using USB-C magnetic connections to switch between your Studio Display (or Pro Display XDR) and source components. Many people have previously had success using connectors from Amazon, normally about $10 each.

I had ordered from at least two different product listings/sellers in the past. I tried to order from each of the same two sellers/product descriptions I'd used previously, and received a different variation that no longer supports video output to the Studio Display or other USB-C monitors I own.

You'll notice the product itself is different, not just the labeling. The new connector has a different female end (more rectangular vs. oval), and has a gold tint vs. silver.

I sent back one set to Amazon as 'item not described' because well it doesn't work. I ordered a second set via a different listing, and received the same new/non-functional product. I will probably keep this, as I do use these connectors for charging-purposes only, and will keep my "good" old ones specifically for video support. Kinda bummed, but I hope this helps someone.

These are the product pages that previously were working versions, but are now sending the ones on the right (not working):

[2Pack Straight+ Extra 2 Plugs]USB C Magnetic Adapter,24 Pins Type C Support Thunderbolt 4,USB4.0, PD 100W Charge,40Gb/s Data Transfer,8K Video Output Compatible with MacBook and More USB C Devices

: ( 2Pack Straight+ Extra 2 Plugs) 24 Pin Straight USB C Magnetic Adapter : DC 20V 100W ：40 Gb/s and 8K video output Package : 24 Pin Straight USB C Magnetic Adapter*2PCS+Extra Plugs*2PCS 2016/2017/2018/2019/2020/2021 MacBook Pro 15inch(87W), MacBook Pro 13inch(61W),iPad Pro 20...

www.amazon.com

YoungSelly Magnetic Adapter and USB C Connector,Support Thunderbolt 4,USB4.0, PD 100W Quick Charge,40Gb/s Data Transfer,8K Video Output Compatible with MacBook and More USB C Devices.(Straight)

Model: 24 Pin Straight USB C Magnetic Adapter Specification: 0.91*1.18*0.4 Input/Output Power : DC 20V 100W Data Transfer：40 Gb/s and 8K video output 2016/2017/2018/2019/2020/2021MacBook Pro 15inch(87W), MacBook Pro 13inch(61W),iPad Pro 2020/2021 USB C laptops and tablets:Compatible wit...

www.amazon.com

View attachment 2097836

I had a set of the old magnetic connectors and the served me well for a good few months until they started to flicker and caused me issues. I got them returned as they're under warranty and ordered a new set. I also noticed that the new ones look different. I tried using them and they can't keep a stable connection. Loads of flickering, screen refreshing, camera not being recognised etc. Everything works perfectly with the cable alone so it's not the cable. I've even tried changing the port I'm using but it makes no difference so it must be the connector.

Unfortunate as these magnetic connectors are convenient but they don't seem well made.

 

[BeatCrazy]

I had a set of the old magnetic connectors and the served me well for a good few months until they started to flicker and caused me issues. I got them returned as they're under warranty and ordered a new set. I also noticed that the new ones look different. I tried using them and they can't keep a stable connection. Loads of flickering, screen refreshing, camera not being recognised etc. Everything works perfectly with the cable alone so it's not the cable. I've even tried changing the port I'm using but it makes no difference so it must be the connector.

Unfortunate as these magnetic connectors are convenient but they don't seem well made.

Are your new ones the version I pictured above?

 

[thedon1]

Are your new ones the version I pictured above?

Not exactly the same (I'm in the UK so different sellers) but from the description, I think they're very similar. The brand for my old and new ones is actually the same, but there must have been some sort of shift in production of these.

 

[citivolus]

The Cable Deconn version arrived today and so far so good! I even connected it to my MBP 14" and Windows laptop using the USB-C cables from the old YIWENTEC version so clearly there was a difference in the units, even if it was just one being defective. Fingers crossed that this lasts!

BTW it seems to take about 7-8 seconds when I switch to my Mac before the desktop shows up on my Pro Display XDR. Is that typical for those of you with this switch?

Just wanted to follow up and report that after four months this setup is still working flawlessly for me. My only complaints are that only one laptop can charge at a time, and the fact that it takes about seven or eight seconds for the display to sync after switching devices. All in all it is by far the most stable set up I have used for this use case.

 

[CatoTheElder]

I have ordered the Deconn adapter as well and it works like a charm! The only drawback to me is that the adapter needs power via USB. But i am even considering buying a second one and chain it, as I have two graphics cards in the MacPro and would like to switch between those two and only then between MacPro and Macbook 1st world problems...

 

[KevinN206]

I have ordered the Deconn adapter as well and it works like a charm! The only drawback to me is that the adapter needs power via USB. But i am even considering buying a second one and chain it, as I have two graphics cards in the MacPro and would like to switch between those two and only then between MacPro and Macbook 1st world problems...

That's awesome. I have a Windows laptop and a MBA M2 that would love to be able to switch. They both have USBC only. Can you provide your exact setup on the Deconn adapter, cables, and how your monitor, keyboard, and mouse are connected?

 

[CatoTheElder]

That's awesome. I have a Windows laptop and a MBA M2 that would love to be able to switch. They both have USBC only. Can you provide your exact setup on the Deconn adapter, cables, and how your monitor, keyboard, and mouse are connected?

Sure, it's pretty straight forward: the Deconn comes with a permanently installed USB-C cable which I connected to the power delivery port of the Display XDR. Two additional USB-C cables are supplied with it that go from the adapter to the Macbook and the MacPro. I have two mice, a Bluetooth magic mouse for the Macbook and a wired one for the MacPro. The keyboard is attached to the Display XDR and is therefore switched with the adapter, as well as a Logitech 4k camera and two additional USB devices. All work fine, bandwidth seems to be no issue. Unfortunately you need USB power for the adapter, but this could be done via the Display XDR if you use an adapter.

And one more thing: the Deconn adapter says "8k" on it... I don't know if this is a newer version or not.
Switching between the two channels takes between 4 and 8 seconds.

 

[twynne]

Sure, it's pretty straight forward: the Deconn comes with a permanently installed USB-C cable which I connected to the power delivery port of the Display XDR. Two additional USB-C cables are supplied with it that go from the adapter to the Macbook and the MacPro. I have two mice, a Bluetooth magic mouse for the Macbook and a wired one for the MacPro. The keyboard is attached to the Display XDR and is therefore switched with the adapter, as well as a Logitech 4k camera and two additional USB devices. All work fine, bandwidth seems to be no issue. Unfortunately you need USB power for the adapter, but this could be done via the Display XDR if you use an adapter.

And one more thing: the Deconn adapter says "8k" on it... I don't know if this is a newer version or not.
Switching between the two channels takes between 4 and 8 seconds.

Very tempted to try this, also for connecting a Windows laptop (currently having only DP out) and a MBP M1 Pro to Apple Studio Display.

Firstly is this the unit you're referring to (https://www.amazon.co.uk/Adapter-Ca...1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1)?

And if so can you see any issues with connecting the Windows laptop using a DisplayPort to USB-C cable like:

uni USB C to DisplayPort Cable 3ft [8K@60Hz 4K@144Hz 5K@60Hz 2K@240Hz], Thunderbolt 3/4 to DP 1.4 Cable 32.4Gbps, Compatible with MacBook Pro 2021/Air 2020, Mac Mini, iPad Pro, iMac, XPS, S21 etc.

uni USB C to DisplayPort Cable 3ft [8K@60Hz 4K@144Hz 5K@60Hz 2K@240Hz], Thunderbolt 3/4 to DP 1.4 Cable 32.4Gbps, Compatible with MacBook Pro 2021/Air 2020, Mac Mini, iPad Pro, iMac, XPS, S21 etc.

www.amazon.co.uk

 

[twynne]

Very tempted to try this, also for connecting a Windows laptop (currently having only DP out) and a MBP M1 Pro to Apple Studio Display.

Firstly is this the unit you're referring to (https://www.amazon.co.uk/Adapter-CableDeconn-Thunderbolt-Compatible-ChromeBook/dp/B076ZKZLXT/ref=sr_1_1_sspa?crid=1RCFC9RAA7TY3&keywords=cabledeconn&qid=1672757002&sprefix=cabledeconn,aps,64&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1)?

And if so can you see any issues with connecting the Windows laptop using a DisplayPort to USB-C cable like:

uni USB C to DisplayPort Cable 3ft [8K@60Hz 4K@144Hz 5K@60Hz 2K@240Hz], Thunderbolt 3/4 to DP 1.4 Cable 32.4Gbps, Compatible with MacBook Pro 2021/Air 2020, Mac Mini, iPad Pro, iMac, XPS, S21 etc.

uni USB C to DisplayPort Cable 3ft [8K@60Hz 4K@144Hz 5K@60Hz 2K@240Hz], Thunderbolt 3/4 to DP 1.4 Cable 32.4Gbps, Compatible with MacBook Pro 2021/Air 2020, Mac Mini, iPad Pro, iMac, XPS, S21 etc.

www.amazon.co.uk

Ok, this method and/or these products completed failed to work with Apple Studio Display - no picture whatsoever. I tried both a Windows laptop (HP Elitebook 840 G3, which has displayport out) <> Displayport 1.4 to Cabledeconn adapter <> ASD thunderbolt port. Also connected the laptop via same cable directly into ASD fails. This may be down to the age of the laptop and the level of DisplayPort it supports, but unclear.

Also tried connected MacBook Pro (2021 M1 Pro) using TB4 cable <> Cabledeconn adapter <> ASD using the cable provided with the Cabledeconn adapter. No picture or reaction whatsoever from the ASD.

Not sure if I've got the wrong adapter, or if it wants different cables. I suspect part of the challenge may lie in the distinction between TB4, TB3, and USB-C.

For clarity, it's this adapter: https://www.amazon.co.uk/CableDecon...2VHC166/ref=psdc_428654031_t1_B076ZKZLXT?th=1

... and this cable: uni USB C to DisplayPort Cable 3ft [8K@60Hz 4K@144Hz 5K@60Hz 2K@240Hz], Thunderbolt 3/4 to DP 1.4 Cable 32.4Gbps, Compatible with MacBook Pro 2021/Air

Thoughts anyone?

 

[edanuff]

Ok, this method and/or these products completed failed to work with Apple Studio Display - no picture whatsoever. I tried both a Windows laptop (HP Elitebook 840 G3, which has displayport out) <> Displayport 1.4 to Cabledeconn adapter <> ASD thunderbolt port. Also connected the laptop via same cable directly into ASD fails. This may be down to the age of the laptop and the level of DisplayPort it supports, but unclear.

Also tried connected MacBook Pro (2021 M1 Pro) using TB4 cable <> Cabledeconn adapter <> ASD using the cable provided with the Cabledeconn adapter. No picture or reaction whatsoever from the ASD.

Not sure if I've got the wrong adapter, or if it wants different cables. I suspect part of the challenge may lie in the distinction between TB4, TB3, and USB-C.

For clarity, it's this adapter: https://www.amazon.co.uk/CableDecon...2VHC166/ref=psdc_428654031_t1_B076ZKZLXT?th=1

... and this cable: uni USB C to DisplayPort Cable 3ft [8K@60Hz 4K@144Hz 5K@60Hz 2K@240Hz], Thunderbolt 3/4 to DP 1.4 Cable 32.4Gbps, Compatible with MacBook Pro 2021/Air

Thoughts anyone?

I think you’re going to have problems with that cable since it has active circuitry that is going to get fooled by the switch. Had problems with a similar cable.

 

[twynne]

I think you’re going to have problems with that cable since it has active circuitry that is going to get fooled by the switch. Had problems with a similar cable.

Thanks, expected as much. Found an article with a link to a specific cable that worked with the ASD and have ordered to try. Will report back.

That doesn’t address the Mac though and why it won’t work via the switch. For that I’m going to try using the usbc cable that came with the switch. Maybe the TB4 that came with the ASD is too much?

 

[edanuff]

Thanks, expected as much. Found an article with a link to a specific cable that worked with the ASD and have ordered to try. Will report back.

That doesn’t address the Mac though and why it won’t work via the switch. For that I’m going to try using the usbc cable that came with the switch. Maybe the TB4 that came with the ASD is too much?

Cables are very finicky with the switch. A lot will not work. Start with trying the ones that came with it to make sure it works with your Mac before trying others. I posted earlier in this thread a few that are known to work as have others.