I just set up UD-ULTCDL docking station, with one of my two new monitors. Pictures render more slowly than they did with my HP docking cube (using the same laptop) which I had to return to my office. Pictures display fuzzy for a split second, then fill in focused.
I’ve seen a lot of discussion on this board about ethernet speeds. How would I test my speed?
What else could be causing this slowness in loading graphics? I want to be able to keep my plugable, but I’ll return it if we can’t get past this annoying downgrade in performance.
Here’s what I’ve got:
An HP Spectre x360 model 136-ae000, from 2018. I have an HP Spectre x360 model 136-ae000, from 2018. Thunderbolt compatible. It has two USB-C ports, one of which supports Thunderbolt 3. The Thunderbolt 3 port supports data transfer up to 40 Gb/s, power delivery, DP1.2, and HP Sleep and Charge12.
Two new HP 24mh monitors. So far I have connected only one to the UD-ULTCDL, via the HDMI cable provided with the monitor. The HDMI port on my new monitors uses the standard HDMI 1.4 version, allowing for 1080p resolution at 75hz refresh rate. My laptop is set to 60Hz refresh rate.
Thank you for reaching out! I’m sorry the UD-ULTCDL isn’t working as expected, and I’ll be happy to assist.
The UD-ULTCDL uses two different technologies to produce video on the connected displays. The HDMI port labelled “HDMI 1” uses DP Alt mode from the connected computer. This essentially works by creating a direct pipeline from the computer’s graphics processor out to the display. The “HDMI 2” and “HDMI 3” ports on the other hand use DisplayLink technology. DisplayLink is a virtual graphics technology which uses software to emulate graphics hardware, and relies primarily on the DisplayLink driver on the computer.
DisplayLink graphics, by virtue of being a virtual graphics technology, generally do not match the performance of a display directly powered by the computer’s internal graphics processor. As a result it’s expected for the performance of the displays connected to HDMI 2 and HDMI 3 to be slightly slower than the display connected to HDMI 1. While the HDMI 2 and 3 ports may not perform as well as the HDMI 1 port, there may still be some steps we can try in order to improve the performance depending on how bad it currently is.
With all this said, can you please specify which HDMI ports on the dock you’re currently using to connect your displays?
One step that’s critical to get the best possible performance for DisplayLink-connected monitors is to ensure that you’re using the latest version of the DisplayLink driver on your computer. To make sure this is the case for you I’d recommend performing a clean reinstallation of the DisplayLink driver. This involves removing the existing DisplayLink driver from the system and installing the latest version. It will also reset the dock’s internal USB hubs which can help resolve issues when one or more functions of the dock aren’t quite working.
Here are the steps to perform a clean reinstallation of the DisplayLink driver in Windows:
Disconnect the dock from the system and please remove the power cable from the dock so it turns off completely (this is important so the unit resets). Please keep it disconnected until the last step
Uninstall any and all software with ‘DisplayLink’ in the title that is present from within the Control Panel > Programs and Features. Don’t worry if these entries are not present or if the process does not work, just move onto the next step
Reattach the power cable to the dock first. Once the dock is powered on, reconnect the dock to your system
In your message you also asked “I’ve seen a lot of discussion on this board about ethernet speeds. How would I test my speed?” It can be complicated to test if an Ethernet port is achieving the full speed possible (more details here: https://kb.plugable.com/question/701269). As an alternative to this, a simple method for testing the dock’s network speed is to use an online network speed benchmarking tool such as www.speedtest.net or www.fast.com. Please note that the maximum speed the dock will be able to get would be capped by the speed of the connection from your Internet Service Provider.
My apologies for the frustration, and thank you for giving us the chance to help.
Thanks for your response early in the morning Pacific Time, Sam!
I will try the process you explained - later today.
I have only one of my two new monitors connected; it’s on HDMI 2.
FYI I ran the PC Mag ethernet speed test twice; downloads 173 and 183 mbps, uploads both 24 mbps.
My new webcam provides a grainy image. (The virtual background is sharp.) The image is grainy even when I plug the camera directly into the USB port on my laptop. Are you aware of any known issues with webcams on a system that’s running DisplayLink software?
Sam, thank you for being candid about the slower performance associated with DisplayLink. What then is the advantage of using a DisplayLink dock vs. Thunderbolt?
I’ll get back to you later today after I implement your recommended process.
Thanks for your reply. Hopefully those speeds are what you expect for your network connection!
The issue of the webcam image being grainy is definitely unexpected. There can sometimes be connectivity issues when using webcams through any USB hub (such as the USB ports on the dock), but I am not aware of issues using webcams specifically when DisplayLink is in use. It’s likely that the dock’s presence irrelevant in this case, especially since the same issue happens when the webcam is connected directly to the computer’s USB ports.
Just to confirm, is the webcam’s image grainy even when the dock is not connected to the computer? The DisplayLink driver would not be in use when the dock is disconnected, so this should be a good test to confirm if its presence on the system is affecting the webcam’s image.
The main advantage of DisplayLink is that it has a much broader compatibility than Thunderbolt. Many DisplayLink-based docks can work on computers that have only USB 3.0 ports (I say many rather than all since some DisplayLink docks like UD-ULTCDL still require DP Alt mode support for one of the video output ports). Some systems may not allow for video output on their USB-C ports, or could be limited to a single external display through these ports. DisplayLink allows for these systems which have ports with limited or no video output to connect to multiple external displays through a single cable despite their limitations.
Please do let us know how the steps I provided work out for you, and feel free to ask if you have any more questions!
I really appreciate your thorough and timely responses. This level of support is a strong plus for sticking with plugable!
Although I can only connect my laptop to the external monitor(s) through a dock, I suppose I can connect the cam to my laptop monitor. I’ll get back to you about how that goes.
Thanks for the explanation of DisplayLink’s advantages. I am wondering if it is right for me, since this laptop was working fine with an HP docking cube from work (until I retired and had to give it back). I have an unopened HP USB-C docking cube with two DisplayPort ports. I plan to return it to Amazon, but maybe I should try it out. At any rate I will first try re-installing the drivers as you recommended.
Thanks Jim! I appreciate the kudos on our support.
Hopefully the steps I provided do the trick of alleviating the performance issues you mentioned. Of course we can also go into more detailed troubleshooting if the issues continue after trying the steps.
HP has a few cube shaped docking stations, each using different technologies to connect the displays (e.g. Thunderbolt, USB-C with DP Alt mode, or DisplayLink). Depending on which dock you had it could also be a DisplayLink-based unit.
In case we find the DisplayLink-based dock isn’t ideal for your use, we do also sell Thunderbolt-based docking stations and I’d be happy to provide a recommendation for one as needed.
Thats sounds good. I’m still also interested in also hearing if the DisplayLink clean reinstallation help with the issues you’re seeing with UD-ULTCDL once you get a chance to try that.
Please let me know if you have any questions in the meantime and I’ll be happy to help!
OK, I have removed, cleaned, reinstalled the graphics drivers. I will test the performance in a moment. But first I want to ask you about the below snip. Do you recommend I get the Display Link Manager? How should I configure my display? (I can share a screen shot of the current settings if that helps.)
After cleaning and reinstalling the drivers, the result is unchanged. New graphics come in fuzzy and then a half second later snap into focus. Once in the cache, they re-display cleanly. Streaming seems to work fine, though I haven’t tried it much. Is this as good as it gets with DisplayLink? It’s something I can live with; it just feels disappointing to revert to worse performance than I had before with an HP dock. Is there anything to be done in the configuration?
We talked about a Thunderbolt dock. I might be interested, if my laptop can make use of one. One or both of my USB-C ports supports Thunderbolt, though my laptop was new in 2018. Below is from the laptop’s User Guide. I just don’t want to spend what I see Thunderbolt 4 docks going for. Thoughts?
Thanks for reaching back out. I’m sorry to hear things still aren’t working as expected after performing the reinstallation.
It’s not necessary to install the DisplayLink Manager, but you have the option to use if it you’d like. The display’s settings can be configured either using the Windows Display Settings, or using the DisplayLink Manager.
From your description it does sound like the dock isn’t performing as we’d expect. The behaviour of the graphics showing fuzzy for a split-second before coming into focus is not one I had heard of previously.
If you’re open to it, I’d like to take a close look into the problem to see what else we may be able to do to resolve it. To do so, our next step is to get some additional information.
Can you please send an email to our direct support email address (support@plugable.com) with “For ticket # 441048” in the subject line? In the email, please include the following information:
The Amazon Order ID number for your docking station purchase. You can find this at www.amazon.com/orders
While the docking station is connected to your PC (even if not working as expected), the output of our diagnostic utility PlugDebug: https://plugable.com/pages/plugdebug
If possible, a short video demonstrating the issue (to help make sure my understanding of it is correct)
This information will help us to determine the next steps.
** Please do not post the above information here in our public forum (it contains personally identifiable information) **
Thanks for offering to further debug this issue. I noticed something: it’s particularly noticeable on the Washington Post site. And often when I click a link on the Post site, it generates a customized ad, which I can imagine would take some band width. On Google images, I found graphics loaded with no visible delay, or sometimes a perceptible but not intrusive very quick delay between fuzzy load and final load. So, it’s most conspicuous on the Post site, and there may be other things going on there.
Just in case, I’m providing the requested info in an email to Support, if you still want to take a look.
