Feedback and wonders - Internet speed x3, screens not auto-starting

[Vadorequest]

Hi!

So, I've bought this DisplayLink PRO which works really great.
I have one MacBook Pro (Apple M1 Pro, 2021), and 4 external screens, so 5 screens in total.

I'm using the ports 1, 2, 3, 4 and the 5th/last USB C port is empty as of now.

I've been surprised by a few things, some good, some bad.

1) Internet speed x3
After branching the DisplayLink PRO using my ethernet cable, the speed has jumped from 885/765Mbps to 2330/2270mbps (up/down). It's almost a x3 speed.

I simply don't understand how that's possible. I've noticed the same increase on 2 different computers (Windows/MacOS). Not that I'm complaining, but it makes me wonder how that's even possible.

Also, the speed increase isn't always present, sometimes during the day it goes back to the previous number (885/765Mbps), during evening/night it's always around x3 (2330/2270mbps), but it also happens during the day, sometimes.

I guess, somehow, the DisplayLink Pro manages to use a part of the network that is unused, but I'd like a more scientific explanation

2) Screens don't auto-turn on
For the 2 screens that are using port 1/2, there is no issue.
But the screens using the DisplayLink feature (3/4) do not come back on when plugging the power cable to the computer, I have to manually unplug/replug the USB C cables connected to the DisplayLink PRO, it's annoying.

It doesn't always happens, it depends on a few things:
- When putting my MacOS to sleep, all screens light up upon going out of sleep, no action needed.
- When uplugging the Power cable of the Mac, I systematically have to replug the cables for USB C 3/4
- When powering down the DisplayLink PRO, I systematically have to replug the cables for USB C 3/4

I'm not sure why it does that, nor how to fix it to have all screens light up automatically without bothering with unplug/replug.

3) Screen 2 displays green "PLUGABLE" image when unplugged, indefinitely
This one is very annoying.
When the HDMI cable to screen 2 (HDMI 2) is plugged, and the DisplayLink PRO is powered, but the Power cable is not connected to any computer, then the Screen 2 shows a green-ish background with Plugable branding, and it doesn't go into sleep mode.

When this happens (typically when I unplug my MacOS to go to work) I also have to power down the DisplayLink PRO so that the screen goes into sleep mode.

4) How much power does the DisplayLink PRO consummes when all devices (computer/screens) are sleeping?
I wonder about this, assuming the computer is 100% charged, does it consummes a lot of power? (should I turn it off?)

I currently don't turn it off (typically during the night, when I could do so) because then I have issue N°2 when waking up and it's annoying.

But I wonder how much that laziness is costing me

[rboerner]

My impression based on your description is that you are using a Plugable UD-7400PD docking station --> https://plugable.com/products/ud-7400pd Please correct me if I am mistaken.

Presuming for the moment that my impression is correct, I would suggest that you contact Plugable directly for assistance --> https://plugable.com/pages/support

[Vadorequest]

Originally Posted by rboerner

My impression based on your description is that you are using a Plugable UD-7400PD docking station --> https://plugable.com/products/ud-7400pd Please correct me if I am mistaken.

Presuming for the moment that my impression is correct, I would suggest that you contact Plugable directly for assistance --> https://plugable.com/pages/support

Indeed, it's UD-7400PD, bought at https://www.ubuy.fr/fr/product/Q7GY6...ion=B0DPGM58S1

I'll contact them there then, thanks.

[Vadorequest]

The support was helpful and helped me solve a few issues.

For your reference, the images with the green background that you are seeing are known as splash screen images for the dock's built-in DockTag technology --> https://kb.plugable.com/question/3251982

In regard to the splash screens, for your reference the 'Welcome' splash screen (that displays the Plugable logo by itself) cannot have its duration altered or be disabled.

At this time the 'USB not connected' splash screen (the one you describe seeing, example shown inline below) cannot be completely disabled, however its duration can be lowered to a minimum value of 3 seconds. While not completely disabled, the much shorter duration will help minimize its presence.

The timing can be changed by using the macOS version of the DockTag On-Screen Display Timing Editor Tool, which is available to download from the UD-7400PD's product page here --> https://plugable.com/products/ud-7400pd#nav-downloads

For your reference, documentation for how to use both the Windows and macOS versions of the tool is available here --> https://kb.plugable.com/3279220

Of course, you can also power off the docking station in order to prevent the splash screens from appearing.

Following the link and installing the software allowed me to reduce the Splash screen from 3600 to 3 seconds.

[Vadorequest]

Originally Posted by Vadorequest

Hi!


1) Internet speed x3
After branching the DisplayLink PRO using my ethernet cable, the speed has jumped from 885/765Mbps to 2330/2270mbps (up/down). It's almost a x3 speed.

I simply don't understand how that's possible. I've noticed the same increase on 2 different computers (Windows/MacOS). Not that I'm complaining, but it makes me wonder how that's even possible.

Also, the speed increase isn't always present, sometimes during the day it goes back to the previous number (885/765Mbps), during evening/night it's always around x3 (2330/2270mbps), but it also happens during the day, sometimes.

I guess, somehow, the DisplayLink Pro manages to use a part of the network that is unused, but I'd like a more scientific explanation

What I eventually realized is that the dock is not “speeding up” the internet like I first thought. It’s simply changing which Ethernet adapter my computer is using.

Before: my “direct Ethernet to the computer” path was actually limited by a 1GbE (1000Base-T) network interface (from the laptop’s built-in NIC).

A 1GbE link typically tops out around ~940 Mbps in speed tests.

After: when I plugged Ethernet into the Plugable UD-7400PD, my OS started using the dock’s 2.5GbE Ethernet adapter (link negotiated at 2500Base-T), so the speed test jumped to ~2.3 Gbps. That’s expected if your router port is 2.5GbE and the endpoint adapter is 2.5GbE.

So the “mystery” was just this: I wasn’t comparing the same class of Ethernet hardware.
I had never been limited in internet speed by my computer before, it always was a router limitation. But the limit exists on both ends.

And so, I've bought a 5G adapter to see if my bandwith isn't actually even faster. I intended to buy a NAS soon and this kind of detail is very important for local internet speed.