Daniel Compton

I recently was looking at how to get more than one display connected to my new M1 MacBook Air. DisplayLink technology had a lot of limitations but was the only option I could see. I looked at different docks and ended up purchasing the ALogic DX3.

These are my thoughts after a few months use. I’ve split the review into DisplayLink and ALogic DX3 sections. Most of my complaints are about DisplayLink and I think would be the same no matter which dock/USB adapter you choose.

Alogic DX3

• The DX3 has 3 DisplayPort ports, but only two of them are DisplayLink compatible. The third one uses Alternate Mode (I think?) over USB-C to pass the DisplayPort signal directly to the monitor. This was good for me as I could make my center display DisplayPort and use DisplayLink on the peripheral display.
• The dock comes with a hefty external power supply almost the size and weight of the dock. The dock has a power button on the front which I thought was unnecessary at first but came in handy as I often need to restart the dock for the Mac to detect one or both of the displays. I’ve had this issue on a 2019 Intel Macbook Pro with directly connected DisplayPort cables so I suspect this may be more of a macOS problem. Having the power button on the front is much more convenient than unplugging the displays or turning the displays off and on.
• I haven’t had any issues with the USB ports. I haven’t pushed them very hard, but I also haven’t noticed anything “wonky” about them either. I have a 10-port USB hub that I plug into the dock and it seems to work fine including for an audio interface.

DisplayLink

• With a 4K display, macOS will let you choose a higher resolution to render at, which it will then downscale to the 4K pixels that are actually on the display. When I first bought the DX3, DisplayLink version 1.4 wouldn’t allow you to do this, the maximum resolution you could pick was 1920x1080 points at 2k (native 4K resolution). When writing this article, I went back to the feature request and found that they had released version 1.5 which was meant to fix this issue. It lets you choose 2560x1440 points but also renders at 2560x1440 pixels, instead of 5120x2880 pixels, downscaled to 4K. The good news is that it looks like they are continuing to work on the software and addressing limitations so hopefully this will be fixed in a future update.
• DisplayLink 1.4 was doing something which prevented you from using Apple Watch to unlock your computer. I discovered that it also stopped you from using your Watch as an admin password. However, the 1.5 update has a checkbox to “Use Apple Watch to unlock on login screen”. When you check that, the Watch unlock appears to work at the login screen and in everywhere else Watch unlock would work. I’m not sure why that wouldn’t just be a default setting?
• Note that you can’t evaluate DisplayLink CPU usage just by looking at the “DisplayLinkUserAgent” process. You also need to look at the WindowServer process, as DisplayLink causes work to be done there when rendering to the virtual display.
• The DisplayLink software could do with more diagnostics on what is happening. Currently you can’t see which displays are controlled by DisplayLink and which are directly connected.
• The DisplayLink software doesn’t seem to have any way to automatically update or even notify you of updates so you’ll need to check the website yourself.
• I haven’t noticed any latency from the compression/decompression signal transfer, but I’m only using the displays for writing code and web browsing so I wouldn’t expect many problems.

Other

• I’ve had a weird bug where sometimes the MacBook display won’t turn on for 10-60 seconds after opening the laptop, even when I’ve been using it only a few minutes prior. I’m not sure if this is related to DisplayLink software or just a macOS bug.

Summary

Overall, the ALogic DX3 dock serves it’s purpose well. If you had any other option, I wouldn’t recommend choosing DisplayLink technology, but with an M1 Mac this your best (and only) option. However, I’m encouraged that DisplayLink are continuing to improve the Mac user experience. When I upgrade to a new MacBook Pro, I’ll either use the DX3 without DisplayLink (if that will work), or sell it and purchase a standard Thunderbolt 4 dock.