TBT3-UDZ, Display Port Monitors and DisplayLink

Hello, I am looking for some guidance and support.

I am interested in a dock / hub with the following features:

  • Charge / power my MacBook Pro which has an M1 Max chip.

  • Connect to two legacy / old Dell DisplayPort monitors at work in Extended Mode WITHOUT the need / use for DisplayLink.

  • Ideally, not have a charging brick (which I know that the TBT3-UDZ does have).

With that in mind I would appreciate answers to the following:

  • Am I correct that the TBT3-UDZ will not require / use DisplayLink to display the two legacy / old Dell DisplayPort monitors in Extended Mode because i) TBT3-UDZ connection is TB3 and ii) MacBook Pro with an M1 Max chip can support up to 3 external monitors?

  • I find the Plugable product offering somewhat overwhelming. Is there a better option / solution that you would recommend noting I want to stay away from DispalLink.

Thank you.

Hello Joel,

Thank you for reaching out on the forums! I’d be happy to help find a solution for your setup.

First, I do want to address that all of our docking stations come with a power brick, so I cannot offer a solution here that does not come with a power brick.

Additionally, the fact that your old monitors use DisplayPort does not neccessitate the need for DisplayLink. DisplayLink is a USB graphics solution that allows displays to be connected over a USB connection rather than a direct video signal. This does not impact whether the DisplayPort connector can be used or not.

With that being said, the TBT3-UDZ is likely your best option here, as it can support two displays via the DisplayPort connector, and it can charge your MacBook with up to 100W of power delivery.

I hope this helps!

Thank you,

Evan

Plugable Technologies

www.plugable.com/support

Evan, much thanks for your response, it is GREATLY appreciated.

Thank you for reaching out on the forums! I’d be happy to help find a solution for your setup.

Great, I welcome the assistance.

First, I do want to address that all of our docking stations come with a power brick, so I cannot offer a solution here that does not come with a power brick.

All good. I figured this was the case as i) it is likely a consequence of the PD feature and ii) the only dock that I could find with an integrated power supply is made by OWC and its port configuration does not meet my needs.

Additionally, the fact that your old monitors use DisplayPort does not neccessitate the need for DisplayLink. DisplayLink is a USB graphics solution that allows displays to be connected over a USB connection rather than a direct video signal. This does not impact whether the DisplayPort connector can be used or not.

I should have been clearer. I would prefer not to need / use DisplayLink which I believe is required with a USB-C dock as USB-C does not have sufficient bandwidth to support two displays over 1 USB-C connection to a laptop without the use of compression / DisplayLink. It is my understanding that this results in the need for a TB3 or TB4 dock. Please confirm / correct my understanding.

With that being said, the TBT3-UDZ is likely your best option here, as it can support two displays via the DisplayPort connector, and it can charge your MacBook with up to 100W of power delivery.

A few follow ups please:

a) Is there a significant difference between the TBT3-UDZ and the TBT4-UDZ. Put another, which do you recommend and why?

b) Is there a concern / problem with using the either the TBT3-UDZ or the TBT4-UDZ horizontally as I have read that there are no rubber feet and thus the dock is prone to both scratch the desk and slip on the desk, neither of which is ideal?

c) Please confirm / correct my understanding that because the dock is TB3 or TB 4 and my laptop has an M1 Max chip, I will be able to get 2 displays in Extended Mode without the need to use DisplayLink?

d) What other, if any, dock should I look at or information should I consider.

Thank you!

Hello Joel,

Thank you for your detailed follow-up; it helps to clarify your requirements and concerns.

Regarding DisplayLink and USB-C/Thunderbolt bandwidth:

You’re partially correct about USB-C and the use of DisplayLink. Traditional USB-C ports without Thunderbolt 3 or 4 may indeed lack the bandwidth to support two high-resolution displays without additional technology like DisplayLink. However, Thunderbolt 3 and 4 ports provide a much higher bandwidth, allowing multiple displays to be connected without the need for DisplayLink’s compression technology. Because of this, we do expect your MacBook Pro to be able to support 2x displays with the TBT3-UDZ without the need for DisplayLink.

The TBT4-UDZ can support up to 4x displays, but only on Windows Thunderbolt 4 hosts, so that would not be applicable with your MacBook. The main relevant difference would be the fact that the TBT4-UDZ has a 2.5 Gigabit Ethernet port, where the TBT3-UDZ has a 1 Gigabit Ethernet port.

I hope this helps!

Thank you,

Evan
Plugable Technologies
www.plugable.com/support

Ethan, much thanks for your continued assistance noting the following:

i) A follow up that was not yet answered, is there a concern / problem with using the either the TBT3-UDZ or the TBT4-UDZ horizontally as I have read that there are no rubber feet on either unit and thus the dock is prone to both scratch the desk and slip on the desk, neither of which is ideal?

ii) I will look at the specifications for the TBT3-UDZ and the TBT4-UDZ tomorrow and decide which to get as I believe there are also some differences between the USB-A port speeds. If the differences are minor then I will likely opt for the TBT3-UDZ as:

  • the differences will not be noticeable on my current MacBook Pro (i.e., TB3 and TB4 have the same bandwidth / speed) meaning there is no benefit to spending the extra money; and

  • the funds can / will be spent on a TB5 dock when I get a new MacBook Pro which because the differences will then be noticeable and worth the additional spend. Comments / thoughts on this approach?

Once again, much thanks for all the help.

Joel

Ethan, good morning.

I need to order a dock later today or first thing tomorrow and would greatly appreciate a response to my above questions which for ease of identification I have reposted below:

  1. Is there a concern / problem with using the either the TBT3-UDZ or the TBT4-UDZ horizontally as I have read that there are no rubber feet on either unit and thus the dock is prone to both scratch the desk and slip on the desk, neither of which is ideal?

  2. Is it correct that the differences between the TBT3-UDZ and the TBT$-UDZ will not be noticeable on my current MacBook Pro (i.e., MacBook Pro is limited to two external displays, TB3 and TB4 have the same bandwidth / speed, etc.) ?

Thank you.

Hello Joel,

  1. Is there a concern / problem with using the either the TBT3-UDZ or the TBT4-UDZ horizontally as I have read that there are no rubber feet on either unit and thus the dock is prone to both scratch the desk and slip on the desk, neither of which is ideal?

The TBT3-UDZ and TBT4-UDZ do not have rubber feet for the horizontal position, but it does come with a stand for the vertical position.

  1. Is it correct that the differences between the TBT3-UDZ and the TBT$-UDZ will not be noticeable on my current MacBook Pro (i.e., MacBook Pro is limited to two external displays, TB3 and TB4 have the same bandwidth / speed, etc.) ?

You likely will not notice much of a difference unless you are able to take advantage of 2.5 Gigabit Ethernet. The details on the USB port speeds are located on the product pages for each of these devices:

https://plugable.com/products/tbt4-udz
https://plugable.com/products/tbt3-udz

The bandwidth for Thunderbolt 3 and Thunderbolt 4 are the same 40Gbps, so there is not much difference there.

Thank you,

Evan
Plugable Technologies
www.plugable.com/support

Ethan, a quick note to thank you for your response.

I purchased the TBT4-UDZ as I believe that it will easier to resell down the road as it will have more appeal to i) Windows users (who can take advantage of the 4 screen capability) and ii) users with 2.5 Gbps internet connections. I also prefer having the host computer connection on the front as this works better for my desk layout.

I will likely be using the TBT4-UDZ horizontally as this too works better for my desk layout. If I do so then I will install small rubber bumpers on the bottom to protect the desk and provide some grip. With a little luck this will work!

Much thanks for all of your input.

Joel

@All, the dock is up and running and working great.

Setup time: plug everything in and get it working, less than 5 minutes (including installing rubber feet); cable management to get everything neat, 90 minutes (but it is super neat)!

Thoughts at the end of day 1: Could not be happier, it simply works thereby allowing me to work. While I know people gripe about the host connection being on the front, I actually prefer it because it provided a neater desk.

Would I change anything:

  1. Downstream TB4 ports, this would make it perfect.

  2. Provide rubber bumpers for the price. While I had them on hand so they were easy to grab, I feel for the price they should be included.

  3. Shorter cable. Truthfully I cannot see anyone needing 3 feet which means there is either a lot of excess cable or, as I need, used a shorter TB4 certified cable.

Happy to answer any questions.