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1x Plugable Triple Display USB-C Docking Station (UD-ULTCDL) With Vertical Stand
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1x 1m USB-C to USB-C Cable With eMarker
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1x 65W (20V 3.25A) Power Supply (100V-240V) With US Power Plug (UL 60950-1 Listed)
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1x Quick Start Guide










Plugable USB-C Triple Display Docking Station
List Price : $265 $189
Amazon Rating :
(667 Reviews)
Features
- TRIPLE MONITOR DOCK—With a compatible USB-C or Thunderbolt 3 laptop or Windows tablet, this dock can charge your device, connect up to 3 monitors, add a Gigabit Ethernet connection, add 3.5mm headphone and microphone jacks, and add multiple USB ports
- HDMI AND DVI/VGA—This dock features 3 video outputs including 1x HDMI 1.4 output capable of 4K 30Hz, 1x HDMI 1.3, and 1x DVI/VGA outputs support 1080p 60Hz
- USB-C FEATURES—USB-C and Thunderbolt 3 ports can enable features such as USB Alternate Mode (Alt Mode) and 60W USB Power Delivery (PD) charging. Support for these features is determined by your laptop manufacturer. See product description for details
- IMPORTANT NOTES—The full product description has important info regarding requirements and limitations of this dock. USB-C required. Not all devices support all features. No HDCP support. Linux, Chrome OS not supported. For Mac-compatible triple display dock, check out UD-ULC4K and UD-3900PDZ
- 2 YEAR WARRANTY—We love our Plugable products, and hope you will too. All of our products are backed with a 2-year limited parts and labor warranty as well as Seattle-based email support

Feature Packed

Charge
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Up to 60W of USB Power Delivery

Display
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1x HDMI 1.4
-
1x HDMI 1.3
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1x DVI

Connect
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4x USB 3.0 Ports
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1x USB-C Port
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1x Gigabit Ethernet
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1x 3.5mm Headphone Jack
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1x 3.5mm Microphone Jack
Operating System Compatibility

Windows

macOS

Chrome OS (Chromebooks) and Linux
In The Box
Item and Quantity | Item Notes |
---|---|
1x Plugable USB-C Triple Display Docking Station | |
1x USB-C to USB-C Cable | |
1x DVI to VGA Adapter | |
1x 65W Power Adapter | Region-specific power outlet adapters are included for purchases in the UK and EU. |
Video
Port | Placement | Specification | Max Resolution and Refresh Rate | HDCP | Chipset |
---|---|---|---|---|---|
1x HDMI (Output) |
Rear | HDMI 1.3 | 1920x1200 @ 60Hz 1920x1200 @ 60Hz1920x1080 @ 60Hz 1600x900 @ 60Hz 1280x1024 @ 60Hz 1280x800 @ 60Hz 1280x720 @ 60Hz 1152x864 @ 60Hz 1024x768 @ 60Hz 800x600 @ 60Hz 640x480 @ 60Hz |
Not Supported | DL-3900 DisplayLink |
1x DVI (VGA with Bundled Adapter) (Output) |
Rear | DVI-I (Dual Link) | 1920x1200 @ 60Hz 1920x1200 @ 60Hz1920x1080 @ 60Hz 1600x900 @ 60Hz 1280x1024 @ 60Hz 1280x800 @ 60Hz 1280x720 @ 60Hz 1152x864 @ 60Hz 1024x768 @ 60Hz 800x600 @ 60Hz 640x480 @ 60Hz |
N/A | DL-3900 DisplayLink |
1x HDMI 4K (Output) |
Rear | HDMI 1.4 | 3440x1440 @ 60Hz 3840x2160 @ 30Hz2560x2160 @ 60Hz 2560x1440 @ 60Hz 2560x1080 @ 60Hz 1920x1080 @ 60Hz 1600x900 @ 60Hz 1280x1024 @ 60Hz 1280x800 @ 60Hz 1280x720 @ 60Hz 1152x864 @ 60Hz 1024x768 @ 60Hz 800x600 @ 60Hz 640x480 @ 60Hz |
Host Dependent | Alt Mode |
Audio
Port | Placement | Connection | Max Bit Depth and Sample Rate | Signal Output | Channels | Chipset |
---|---|---|---|---|---|---|
Headphone Jack Line Out |
Front | 3.5mm (TRS) | 16-bit 48KHz | Analog | 2 | DL-3900 DisplayLink |
Microphone Jack Line In |
Front | 3.5mm (TRS) | 16-bit 48KHz | Analog | 2 | DL-3900 DisplayLink |
HDMI 4K Output |
Rear | HDMI | Host Dependent | Digital | Host Dependent | |
HDMI Output |
Rear | DisplayLink HDMI | 16-bit 48KHz | Digital | 6* | DL-3900 DisplayLink |
Power
Port | Placement | Power Host / Device | Connection Type | Notes | Voltage | Amperage | Wattage |
---|---|---|---|---|---|---|---|
Power Supply | Rear | Device | Region-specific Power Adapter | 20.0V | 3.0A | 60.0W | |
USB-C to Host | Rear | Host | USB-C Power Delivery | Check Compatibility Table | Up to 20.0V | Up to 3.0A | Up to 60.0W |
USB To Devices
Port | Placement | Version and Link Rate | Features | Voltage | Amperage | Wattage |
---|---|---|---|---|---|---|
3x USB-A | Rear | USB 3.0 (5Gbps) | 5V | 900mA | 4.5W | |
1x USB-A | Front | USB 3.0 (5Gbps) | Battery Charging 1.2 | 5V | 1500mA | 7.5W |
1x USB-C | Front | USB 3.0 (5Gbps) | 5V | 1500mA | 7.5W |
Connection To Host
Port | Placement | Version and Link Rate | Features |
---|---|---|---|
1x USB-C | Rear | USB 3.0 (5Gbps) | USB Power Delivery |
Wired Network
Port | Placement | Version and Link Rate | Features | Chipset |
---|---|---|---|---|
DisplayLink Gigabit Ethernet | Rear | 1000BASE-T | DL-3900 DisplayLink |
Included Cables
Port Type (Side 1) | Cable Specification | Port Type (Side 2) | Cable Length | External Power for Cable |
---|---|---|---|---|
1x Male USB-C | USB 3.0 (5Gbps) | 1x Male USB-C | 1.0m/3.3ft | No |
1x Male IEC Type B | 1x Male IEC C5/C6 | No |
Device Compatibility
While Plugable's docking stations utilize the vast majority of USB-C features including alternate mode video output and USB Power Delivery charging. However, not all host systems support these features. In addition to features that are specific to USB-C, Plugable's USB-C docking stations feature DisplayLink technology which may have compatibility issues on some hosts.
Windows
2. Navigate to your Downloads folder and launch the DisplayLink installation program.
3. Connect the dock when prompted to do so during installation. (If installing drivers before receiving the unit, click Skip when given the option during device detection.)
Filter Help Articles and Frequent Questions by Category
Articles
USB Port Types
USB-A
pietz, CC BY-SA 3.0 , via Wikimedia Commons
This is the standard USB connection that most computers offered prior to the introduction of USB Type-C (USB-C). Even after the introduction of USB Type-C, this is still quite common.
It can provide data transfer rates up to the USB 3.1 Gen 2 (10 gbps) specification depending on the host and device, but does not directly support video in the way that USB-C Alternate Mode does. This limitation makes DisplayLink USB graphics adapters and docking stations ideal on systems that do not have USB-C, or in instances where more displays are needed beyond available video outputs of a PC.
USB-B
Fred the Oyster, CC BY-SA 4.0 , via Wikimedia Commons
IngenieroLoco, CC BY-SA 4.0, via Wikimedia Commons
This type of connection comes in a couple different styles depending on whether USB 3.0 and higher transfer rates are supported (bottom graphic). Usually this type of connection is used to plug into USB devices that do not have a fixed cable connected, such as USB docking stations, USB hubs, printers, and others.
USB Mini-B
Fred the Oyster, CC BY-SA 4.0 , via Wikimedia Commons
One of the first connectors for charging a smartphone, wireless game controller (such as the Sixaxis and DualShock 3), and other small devices such as external hard drives. Not commonly used today, but is still used in some cases. Most devices using USB Mini B are using USB 2.0, though a USB 3.0 variant does exist. This specification also added USB On-The-Go (OTG) functionality, though it is more commonly implemented with Micro USB.
USB Micro-B
Fred the Oyster, CC BY-SA 4.0, via Wikimedia Commons
IngenieroLoco, CC BY-SA 4.0 , via Wikimedia Commons
A smaller connector that serves many of the same uses as the Mini B connector, with added optional features such as Mobile High-Definition Link (MHL) to allow devices like smartphones to output video to larger displays without requiring a dedicated port for video output.
The larger variant of USB-B is most commonly used for external hard drives for higher 5Gbps transfer rates.
USB-C, Thunderbolt™ 3, and Thunderbolt™ 4
Niridya , CC0, via Wikimedia Commons
The most recent USB connection, USB Type-C (USB-C), represents a major change in what USB can do. The connector is smaller, can be connected in two orientations, is able to carry substantially more power and data, and can directly carry video signals of multiple types (HDMI, DisplayPort, etc.) Intel has also adapted the USB-C connector for use with Thunderbolt 3 and Thunderbolt 4.
It is important to note that while all Thunderbolt 3 and Thunderbolt 4 connections are USB-C, not all USB-C connections can be used with Thunderbolt 3 or Thunderbolt 4 devices.
More details regarding physical USB connections can be found on Wikipedia . The graphics depicted here are adapted from Wikimedia Commons by various artists under the Creative Commons Attribution-Share Alike 3.0 Unported license.
My DisplayLink-based USB Docking Station or USB Video Adapter Is Not Working As Expected
When a Plugable DisplayLink device is not working as expected with a Windows system, the best practice is to disconnect the device from the host system (and remove it's external power source, if it has one) and perform a 'clean' manual installation of the latest version we recommend of the required DisplayLink software driver to help ensure both are in a good state. To do so, please follow these steps:
- Disconnect the Plugable USB docking station or video adapter from the host system. If the product you are using has an external power adapter (for example a USB docking station), please also disconnect the power adapter from the product so that the unit resets. Please keep everything disconnected until prompted
- Uninstall any and all software with 'DisplayLink' in the title that is present from within the Control Panel Programs and Features (Apps and Features in Windows 10). Don't worry if these entries are not present or if the process does not work for any reason, just move onto the next step
-
Download and run the DisplayLink Installation Cleaner utility
- We have a short video that demonstrates this process
- Once the cleaning utility has completed running, restart the host system (even if not prompted to)
- Download and install the latest version (that we recommend) of the DisplayLink software driver
- If you disconnected the power adapter from your product in step one, please reconnect it so the device powers on, then reconnect the product to the host system. If the product is still not working as expected, please restart the host system one more time.
If, after having completed this process, your Plugable DisplayLink device is still not working as expected, please reach out to us directly via support@plugable.com with the output of our PlugDebug diagnostic utility and we will be happy to help.
Blue Light Reduction Applications Are Not Working While Connected to my DisplayLink USB Dock or Adapter
The DisplayLink driver does not currently support this type of color adjustment. As a result, applications like f.lux, Night Shift or Night Light will not affect displays connected to a DisplayLink-based docking station or video adapter.
** f.lux has added there own proprietary support for DisplayLink-based devices in the latest version of there utility. However, this capability is not supported by Plugable or DisplayLink directly.
I Can't Use My Intel, NVIDIA, or AMD/ATI Graphics Utility to Manage the Monitors Connected to My DisplayLink-Based Docking Station/Graphics Adapter. Why?
The graphical software utilities provided by Intel, NVIDIA and AMD/ATI are designed to only recognize and work with graphics adapters made by their respective manufacturers. As a result, they will not recognize USB-attached displays connected to a DisplayLink-based docking station or graphics adapter.
It is recommended to use the facilities built-in to Windows to manage the connected displays. These would be the ‘Display Settings’ application on Windows 10 and ‘Screen Resolution’ application on Windows 8.1 and 7. Both of these applications are available by right-clicking on empty space within the Windows desktop and selecting the appropriate choice from the context menu that appears.
Note: Intel has released an updated 'Intel Graphics Command Center' application that can recognize DisplayLink-attached displays and configure them to a certain extent. However, some of the features within the Intel Graphics Command Center application that are specific to Intel graphics adapters may not work on a DisplayLink-attached display.
Why Doesn't the "Display Color Calibration" Tool in Windows Affect the Display(s) Attached to My DisplayLink-Based Docking Station/Video Adapter?
The DisplayLink driver does not support color calibration functionality of any kind. Most monitors have built-in controls that can be used to adjust the characteristics of the display, though we realize this approach may not be ideal in all cases. For environments that necessitate near-perfect color reproduction and display calibration capabilities via software, a dedicated graphics card is recommended.
Are Plugable USB Video Adapters or Docking Stations Based on DisplayLink Technology Compatible With Touchscreens?
Touchscreens that do not require drivers and use the host’s operating system’s built-in USB Human Interface drivers (HID) to record touch inputs can be made to work with our products, however Plugable does not provide support for doing so due the complexity of multi-monitor touch screen setups.
If I Add a DisplayLink-Based Docking Station or Graphics Adapter to My System, Will That Prevent My System’s Built-In Video Outputs From Working?
No, the DisplayLink device's presence on your system will not preclude the use of any of your system’s built-in video outputs.
Are Powerline Network Adapters Supported in Conjunction With the Ethernet Port Within My DisplayLink-Based Docking Station or Video Adapter?
The use of Powerline-based network adapters in conjunction with the Ethernet port within our DisplayLink-based docking stations or video adapters is not supported.
Can I Adjust the Brightness of a Display Connected to My DisplayLink-Based Docking Station or Video Adapter via the Windows ‘Display Settings’ Application?
Windows does not have the ability to adjust the brightness of a display connected using DisplayLink technology. We recommend making use of the display’s internal on-screen menu options in order to adjust the display's brightness.
Can I Use My DisplayLink-Based Docking Station in Conjunction With a KVM (Keyboard, Video and Mouse) Switch?
No, Plugable does not recommend or support using our DisplayLink-based docking stations with a traditional KVM switch. If you simply need to share the dock between two systems, the dock can be manually disconnected from the first system and then manually connected to the second system.
For those using our USB 3.0 DisplayLink docking station products that would like a more permanent solution that does not require disconnecting the unit from the host system, our Plugable USB 3.0 Sharing Switch can be used as an alternative to share the dock between two systems (please keep in mind that the dock can only be used by one system at a time).
Troubleshooting Wi-Fi, Wireless Keyboard, and Mouse Issues While Using USB Docking Stations Based on DisplayLink Technology
Wi-Fi Performance Issues
Any time a USB 3.0 device is connected to a laptop system, there is a potential that the USB 3.0 connection can generate interference that can affect the performance of the laptop's built-in Wi-Fi adapter.
This behavior is not specific to Plugable products, and Intel has published a white paper on the topic for those who are curious about the technical details.
So now that we know that this can happen with any type of USB 3.0 connection, how do we solve the problem should it occur? Every person’s setup can be a little different so there will never be one definitive solution, but a few simple approaches can solve the problem in most cases:
- Option One—Move the device as far as away from the system as the USB cable will allow. This will try and ‘move’ the signals from both the USB connection and the Wi-Fi physically further apart. As a corollary to this, if the dock is located very close to the Wi-Fi router itself, placing more distance between the two can help.
- Option Two—Switch to a different USB port on the system, preferably one on the opposite side of the laptop. This employs the same approach as option one, in that physically separating the two signals (in this case the physical proximity of the USB connection and the internal Wi-Fi antennas within your system) can help. If your system has both USB 3.0 and USB 2.0 ports, try using the USB 2.0 port first.
- Option Three—Use a USB 2.0 cable, like one used connect to a USB printer, instead of a USB 3.0 cable. All USB 3.0 devices should be backward compatible with a USB 2.0 cable, and when a device is connected at USB 2.0 speeds there is no possibility for the interference.
- Option Four—Switch to using a 5GHz Wi-Fi connection. As the name implies, there are two common sets of frequencies used by most Wi-Fi networks (2.4GHz and 5GHz). If both your wireless router and the wireless network adapter in your system support a 5GHz connection (they both need to, one is not enough), connecting to your Wi-Fi in that manner will prevent the interference from happening due to the two very different frequencies in use.
- Option Five—If using a 5GHz connection is not possible, changing the ‘channel’ of a 2.4 GHz connection can help. Within the 2.4GHz band used for Wi-Fi, there are eleven different channels each using a slightly different frequency. The three most commonly used ones in the United States are channel 1, 6 and 11. Using the manual for your wireless router as a guide, switching channels can potentially help. Ideally you would want to switch the channel to the opposite end of the spectrum for the best results, for example if you are on channel one already try switching to channel eleven or vice-versa
Wireless Mouse or Wireless Keyboard Performance Issues (Radio Frequency Interference)
While the items listed above can help with Wi-Fi interference, there is another type of interference that can sometimes cause problems with wireless keyboards and wireless mice which we refer to as Radio Frequency (RF) interference.
To expand further, the USB wireless receiver 'dongles' used by many wireless keyboards and wireless mice operate within the same 2.4GHz radio frequency range as many Wi-Fi adapters.
If a USB 3.0 connection is generating interference, this can affect the behavior of a wireless keyboard or wireless mouse. This behavior typically manifests as inconsistent mouse movement and/or inconsistent or sporadic keystroke registration.
In general there are two methods to mitigate this behavior should it occur:
- RF Option One—Reconnect the USB wireless receiver 'dongle' to one of the USB Docking Station's USB 2.0 ports (if the dock has USB 2.0 ports), furthest away from the USB 3.0 host connection cable. Moving the USB receiver to a USB 2.0 port typically mitigates this interference.
- RF Option Two—In rarer cases when moving the receiver is not enough or if the product in question does not have a USB 2.0 port, adding a short USB 2.0 extension cable can also help mitigate the behavior. In many cases wireless mice or keyboards include such a cable for this very reason, but if one is not available our USB2-2PORT is a good alternative solution.
Does Plugable Support macOS With Our DisplayLink-Based Products?
Our DisplayLink-based products are supported with macOS albeit with some potential limitations.
As of this writing, there are two different versions of the macOS driver that have been released by DisplayLink (the separate company that makes the primary chip within our DisplayLink-based products, and who also develops the software driver).
A ‘legacy’ version which uses a kernel extension in order to provide its functionality, and a newer ‘DisplayLink Manager Graphics Connectivity’ App which utilizes a new architecture that does not rely on a kernel extension to provide its functionality.
The choice of which driver to use is ultimately determined by one’s OS version and individual specific requirements, since each version offers different capabilities and operating system compatibility. We have provided a comparison table below that highlights their differences in an effort to help our customers make an informed decision.
New DisplayLink Manager Graphics Connectivity App |
‘Legacy’ DisplayLink driver |
|
Supported operating system versions |
macOS 10.15 Catalina and macOS 11 Big Sur |
macOS 10.14 Mojave and macOS 10.15 Catalina |
Ease of installation |
Straightforward |
Can sometimes be more difficult, as compared to the new App |
Supports closed-display mode (aka clamshell mode -> https://support.apple.com/en-us/HT201834 ) |
No** | Yes |
Supports display ‘rotation’ |
No with macOS 10.15 Catalina Yes with macOS 11 Big Sur on Intel-based systems No with macOS 11 Big Sur on Apple CPU-based systems |
Yes |
Supports macOS ‘Login screen’ |
Yes, with additional ‘Login screen’ application installation |
Yes |
Manageability |
Via DisplayLink icon within the Apple Menu bar |
No management application |
Development status |
Actively being developed |
Being phased out due to changes within macOS |
** Closed-display mode (aka clamshell mode or 'lid closed' operation) is supported on Macs using Apple M1 processors when an external power source is connected (e.g. Apple-branded power adapter or a docking station with host charging capability) on macOS Big Sur version 11.1 and later. Clamshell mode is not supported on Intel-based Macs
DisplayLink Manager App Installation Instructions on macOS 10.15+
Unsure which version of macOS you have installed? Click on the ‘Apple’ icon in the menu bar on your desktop and select ‘About this Mac’. A new window will open and display the system’s macOS version.
How to install the DisplayLink Manager application
1. Download the DisplayLink Manager from our drivers page here: https://plugable.com/pages/displaylink#macos
2. Open the DisplayLink Manager Graphics Connectivity 1.x.pkg

3. Click ‘Continue’ on ‘Introduction’ page

4. Click ‘Continue’ on ‘Licence’ page

5. Click ‘Agree’ when prompted

6. Click ‘Install’ on ‘Installation Type’ page

7. Input your password when prompted

8. When installation finishes click ‘Close’ on ‘Summary’ page


9. Click’ Move to bin’ when prompted

How to use DisplayLink Manager?
The following steps are to be followed once after installing the app.
1. After installing the DisplayLink Manager and connecting the Plugable DisplayLink product to your laptop please press ‘command’ + ’space’ and type in DisplayLink Manager, click on the application to open it

a. Alternatively you can go to the Applications folder in Finder and click on the DisplayLink Manager there

2. When first opened, DisplayLink Manager will ask you to turn on notifications for the app. Click on the notification below when it shows up. It will open a Notifications window.

3. Turn on ‘Allow Notifications’ for DisplayLink Manager

4. The DisplayLink Manager logo will show in the Menu Bar. It will be grey when the dock is disconnected (Connection status will show: No monitor detected) and white when connected (Connection status will show: Monitor detected).


5. Select “Launch automatically after logging-in” for the software to start automatically every time you log-in.
NOTE: this is not compulsory but recommended to save you from repeating step 1 each time you login.

6. Screen Recording
NOTE: From macOS Catalina 10.15, the operating system requires the user to permit "Screen Recording" in order for DisplayLink based devices (like Plugable UD-3900) to work properly. The message is generated by the OS and the screen is not actually being recorded by DisplayLink. Approving it enables the DisplayLink driver to access the pixels it needs to render a mirrored or extended screen and send the pixels over USB from your computer to the DisplayLink display. DisplayLink Manager does not store or record any screen content.
a. If you enabled notifications in step 3 you will see the below message if Screen Recording is switched off

b. This message will also show in the DisplayLink Manager app window and there will be an exclamation mark ‘!’ next to the DisplayLink Manager icon.

7. To enable “Screen Recording”
a. Go to System Preferences and click on Security & Privacy

b. In the ‘Privacy’ tab scroll down to ‘Screen Recording’ and click on the padlock to make changes

c. Enter password to allow the system to make changes

d. Tick the box next to ‘DisplayLink Manager’ and click ‘Quit and reopen’ when prompted.

e. Click on a padlock to save the changes.

Other functions of the DisplayLink Manager
Login screen extension (Optional)
This enables the external screens to be available on the login screen prior to the app loading after logging into your account.
1. Download the Login Screen Extension from the link available on the front page of the DisplayLink Manager.

2. Install the extension.

3. Once the installation is complete the extension will show as ‘Installed’

Support
NOTE: Opening a ticket through the Support tab will contact the DisplayLink engineering team in Europe. We recommend contacting support@plugable.com if you have any questions or issues.
Does the HDMI 1.4 Port Support 4K Resolution at 60Hz?
No. The port complies with HDMI 1.4, and as such 3840x2160 (4K is only achievable at 30Hz. 2560x1440 and all lower resolutions will display at 60Hz.
Can I Connect a DisplayPort (DP) Monitor to the HDMI Port on This Device Using an Adapter or Cable?
No, this is not possible. Please note that DisplayPort to HDMI cables (as with any cable involving protocol/signal conversion) are not bidirectional adapters. Such cables will not allow an HDMI output port (such as those on the dock) to function with a DisplayPort input on a monitor.
How to Configure/Adjust Multiple Monitors Using a Windows System
We have a produced a series of short videos that introduce the general concepts of multi-monitor setups in Windows, how to make changes to the way things behave, as well as how to solve common problems.
Direct links to the introductory videos our customers have found the most useful are:
- Introduction to Multiple Displays in Windows
- Common Multi-Monitor Problem—Spatial Orientation
- How To Make a Display the ‘Main’ Display in Windows
- Multi-Monitor Problem—Spatial Orientation Part Two
- Introduction to Display Scaling in Windows
We also maintain a playlist that contains all of the multiple monitor tutorial videos we have made .
Understanding and Troubleshooting Network Performance
Computer networking is a complex topic. In this article, we'll be taking a deep dive on the nuances of network performance for those who need some additional explanation while striving to be concise, and to educate users of various experience levels relating computer hardware and computer networking.
If you just need to know how to perform a network performance test/benchmark, jump down to configuring iPerf.
Core Network Concepts
LAN vs WAN
With regards to network performance, it is crucial to first separate whether an issue is with Wide Area Network (WAN) performance, or if the issue is with Local Area Network (LAN) performance.
Your LAN is essentially the network inside your home or business. Many homes use a combination modem/router device provided by their Internet Service Provider (ISP). In some cases, especially in businesses, you may have a separate modem and router, along with other equipment connecting to the router such as a network switch.
Your modem, and the connection it establishes to your ISP—whether through coaxial cable, fiber, phone lines, or long-range wireless—essentially marks the point between the WAN and the LAN. The connection your modem makes to your ISP is the WAN, and any devices you connect through your router behind that modem belong to the LAN.
Link Rate
Almost every type of connection your computer makes to any piece of hardware will have a link rate of some kind. The link rate establishes how fast data can possibly be transferred across any given connection, but it does not guarantee how fast the hardware on either end of the connection will actually transfer data.
The concept of link rates, and their related bottlenecks, is likely best conveyed by giving an example of what connections might be involved in transferring a file from one computer on your LAN to another.
- 800Mbps—The file source is a USB 3.0 thumb drive capable of 100MB/s (800Mbps) read/write.
- 480Mbps—The USB 3.0 thumb drive is plugged into a USB 2.0 port on the PC, which has a maximum throughput of 480Mbps
- 1000Mbps—PC1's Ethernet connection establishes 1Gbps (1000Mbps) link to the router via Ethernet
- 300Mbps—The router connects to a second PC (we'll refer to this as PC2) via Wi-Fi, and it has established a 300Mbps link to the Wi-Fi adapter on PC2
- 480Mbps—The Wi-Fi adapter on PC2 is connected via a USB 2.0 port. The link rate of the USB connection to PC2 is at 480Mbps
- 6000Mbps—PC2 is going to store the file on an internal hard drive with a link rate of 6Gbps
- 1600Mbps—File Destination: SATA hard drive capable of 200MB/s (1600Mbps) read/write.
Following this chain, we see that 300Mbps is the slowest link rate established. This means that, regardless of the link rates established elsewhere, the absolute maximum the data can possibly be transferred is 300Mbps.
if we were to change the Wi-Fi connection to a wired Ethernet connection capable of 1Gbps, our performance bottleneck would then become the USB 2.0 connection to the USB drive where the file is stored.
Ports and Interfaces
Interfaces
A network interface represents connections, whether wired or wireless, that are made to form a network between devices.
Ports
Some may refer to physical hardware connections as "ports". For the purposes of networking, ports are logical constructs that can also be referred to as "network ports". Each network interface has 65,535 of these logical ports. Each port on a network interface is a separate data connection.
Benchmarking Network Adapter Performance
To properly benchmark network adapter performance, we need to:
- Use a simple LAN configuration
- Eliminate bottlenecks, especially link rate bottlenecks
Websites like speedtest.net, fast.com, and other performance tools in your web browser are going to use your WAN connection, and are not appropriate for determining if a network adapter is working well.
Transferring files from one computer to another on your LAN is typically not the best way to benchmark a network adapter. File transfers are bottlenecked by a number of things, including performance limitations of the disk the data is on, and often times a lack of establishing parallel network connections to perform the task.
One of the most accurate ways to benchmark network performance on a LAN is by using iPerf . To more effectively benchmark network adapter performance, it is best to establish a point-to-point connection between two PCs, rather than connecting through a router or switch.
Configuring iPerf
To test a connection using iPerf, you'll need at least two network interfaces, and preferably two computers. You'll also need to know the IP (Internet Protocol) address assigned to each network interface . One network interface will function as an iPerf server, and the other network interface will function as an iPerf client. Lastly, you'll need to download the version of iPerf 3.x that's appropriate for your computer's operating system and extract/install it .
Windows
- Make sure the drivers for both network interfaces involved in the test are using up-to-date drivers. Drivers for Plugable products can be found here.
- Download and extract iPerf for Windows
- Open Command Prompt
- Press Windows Key + R or + R, then enter
cmd
in the window that appears - Search the Start Menu for
Command Prompt
, and open it
- Press Windows Key + R or + R, then enter
- Navigate Command Prompt to the directory the directory where iPerf is located
- The
cd
command is for 'change directory'- If you have a folder named 'iperf' on your Windows desktop, you can reach it in command prompt with the command
cd %USERPROFILE%\Desktop\iperf
- If you have a folder named 'iperf' on your Windows desktop, you can reach it in command prompt with the command
- The
- Run iperf in server mode via Command Prompt
iperf3.exe -s
macOS
- Usually it is best to install iperf on macOS using brew in Terminal
- Make sure the drivers for both network interfaces involved in the test are using up-to-date drivers
- Open Terminal
- Run iPerf in server mode
iperf3 -s
Linux
- Usually it is best to install iperf using the package manager in your Linux distro. For example, in Ubuntu, use
apt
: -
sudo apt install iperf3
- Make sure the drivers for both network interfaces involved in the test are using up-to-date Drivers
- Open Terminal
- Run iPerf in server mode
iperf3 -s
Next, you'll need to run iPerf in client mode, targeting the IP address of the server/interface where iPerf is running in server mode. Additionally, we'll run the test for 30 seconds using -t 30
and with four parallel connections using -P 4
. Running 4 parallel connections is optimal for saturating a network link.
Windows
- Open Command Prompt
- Press Windows Key + R or + R, then enter
cmd
in the window that appears - Search the Start Menu for
Command Prompt
, and open it
- Press Windows Key + R or + R, then enter
- Navigate Command Prompt to the directory the directory where iPerf is located
- The
cd
command is for 'change directory'- If you have a folder named 'iperf' on your Windows desktop, you can reach it in command prompt with the command
cd %USERPROFILE%\Desktop\iperf
- If you have a folder named 'iperf' on your Windows desktop, you can reach it in command prompt with the command
- The
- Run iperf in client mode via Command Prompt (replace 192.168.0.200 with the IP address of the server/interface where iPerf is running in server mode)
iperf3.exe -c 192.168.0.200 -t 30 -P 4
macOS / Linux
- Open Terminal
- Run iPerf in client mode (replace 192.168.0.200 with the IP address of the server/interface where iPerf is running in server mode)
iperf3 -c 192.168.0.200 -t 30 -P 4
iPerf should start performing a network performance test. If the test fails to start, make sure that iPerf is not being blocked by your PC's/Mac's firewall.
Why iPerf is Ideal for Benchmarking
Unlike a file transfer, iPerf runs in memory on the PC and generates data to send using the CPU directly. This alleviates potential bottlenecks generated by storage devices, and allows you to explicitly control how many parallel connections are being used to transfer data rather than being unsure if parallel network connections are being used by other means.
Conclusion
There's a lot more to networking that isn't covered in this article, but we hope this helps explain enough to get an accurate measure of your network performance.
If you need assistance with your Plugable product that features network connectivity, please contact us for further assistance.
No Sound? How to Change Your Default Audio Device to Your Plugable Product
Whether you're on Windows, macOS, or Linux, it's common to add new audio devices to your computer.
Some examples of additional audio devices you may want to switch to include:
- Bluetooth headsets, headphones, and speakers
- Speakers built into a display, such as a TV or monitor
- A USB sound card, digital audio converter (DAC), or analog to digital converter (ADC)
- USB microphones
- Audio jacks on a docking station
These steps don't apply to the Plugable Performance NIX HDMI Capture Card (USBC-CAP60).
Here are the steps that you need to set a new default audio recording or output device on different operating systems.
Set Audio Output Device
Set Audio Recording Device
Set Default Playback Device in Windows
- Check that your device is properly connected, and that any necessary drivers are installed
- It is also a good idea to make sure that your sound device is turned on, and that the device's volume control is not at the absolute minimum setting
- Right-click on the speaker symbol in the Windows taskbar/system tray
-
Windows 7/8.x—Select Playback Devices. The Sound window will open with the Playback tab highlighted
-
Windows 10—Select Open Sound Settings then click the link under 'Related Settings' for Sound Control Panel, then click the Playback tab
- Alternatively, after selecting Open Sound Settings, use the dropdowns under the Output header
-
Windows 7/8.x—Select Playback Devices. The Sound window will open with the Playback tab highlighted
- Find your device in the window
- A Plugable USB 3.0 docking station or sound-enabled display adapter will appear as Plugable Audio
- A Plugable USB 2.0 docking station will appear as USB Multimedia Audio Device
- A Plugable USB Audio adapter will appear as USB Audio Device
- Right-click on the device you found in step 3 and select Set as Default Device. A check mark should appear next to your device, and sound should now play through it
- Click OK to exit the window
Additional Configuration for Bluetooth
Please see our pairing and configuration guide for Bluetooth devices.
Set Default Playback Device in macOS
- Open System Preferences
- Click Sound
- Select Output
- Select the most appropriate device
- A Plugable USB Audio adapter will appear as USB Audio Device
Set Default Playback Device in Linux
- Ensure that you audio device is connected to the PC
- If the audio device is self-powered, it is a good idea to make sure that it is powered on, and that the device's volume control is not at the absolute minimum setting
- Launch the 'Settings' application in your distro
- Go to the 'Sound' option
- Find the dropdown for your 'Output Device', and change it to your preferred output device
- For additional sound device controls, you may want to consider using Pulseaudio Volume Controls (package name pavucontrol)
Set Default Recording Device in Windows
- Check that your device is properly connected, and that any necessary drivers are installed
- It is also a good idea to make sure that your sound device is turned on, and that the device's volume control is not at the absolute minimum setting
- Right-click on the speaker symbol in the Windows taskbar/system tray
-
Windows 7/8.x—Select Recording Devices. The Sound window will open with the Recording tab highlighted
-
Windows 10—Select Open Sound Settings then click the link under 'Related Settings' for Sound Control Panel, then click the Recording tab
- Alternatively, after selecting Open Sound Settings, use the dropdowns under the Input header
-
Windows 7/8.x—Select Recording Devices. The Sound window will open with the Recording tab highlighted
- Find your device in the window
- A Plugable USB 3.0 docking station or sound-enabled display adapter will appear as Plugable Audio
- A Plugable USB 2.0 docking station will appear as USB Multimedia Audio Device
- A Plugable USB Audio adapter will appear as USB Audio Device
- Right-click on the device you found in step 3 and select Set as Default Device. A check mark should appear next to your device, and sound should now play through it
- Click OK to exit the window
Additional Configuration for Bluetooth
Please see our pairing and configuration guide for Bluetooth devices.
Set Default Recording Device in macOS
- Open System Preferences
- Click Sound
- Select Input
- Select the most appropriate device
- A Plugable USB Audio adapter will appear as USB Audio Device
Set Default Recording Device in Linux
- Ensure that you audio device is connected to the PC
- If the audio device is self-powered, it is a good idea to make sure that it is powered on, and that the device's volume control is not at the absolute minimum setting
- Launch the 'Settings' application in your distro
- Go to the 'Sound' option
- Find the dropdown for your 'Input Device', and change it to your preferred input device
- For additional sound device controls, you may want to consider using Pulseaudio Volume Controls (package name pavucontrol)
Why Isn’t My Plugable Dock Charging My Laptop?
Please note that not all USB-C ports on a computer support charging. Verify if your computer supports Power Delivery (PD) over USB-C and also identify which port has this functionality (if multiple USB-C ports are available).
Otherwise, please check that the docking station is powered on. Depending on the model of the dock, you should see a blue or white light which indicates the dock is powered.
Please contact us at support@plugable.com for further assistance.
My Docking Station/Adapter Works Well With My Windows Laptop, but When I Close the Lid the Displays and Laptop Turn Off. How Do I Fix This?
Windows has special power management settings that control what happens when the laptop lid is closed. If this happening, these settings need to be changed. Please right-click on the Start button and select ‘Power Options’ from the menu.
From the choices present on the left-hand side of the 'Power Options' window, please click on ‘Choose what closing the lid does’.
Make sure the setting for ‘When I close the lid’ under the ‘Plugged In’ column is set to ‘Do Nothing’.
Click the ‘Save Changes’ button and restart the system (making sure that the laptop’s power adapter is also connected) and test the behavior again.
Legacy macOS DisplayLink Driver Installation Instructions
Unsure which version of macOS you have installed? Click on the ‘Apple’ icon in the menu bar on your desktop and select ‘About this Mac’. A new window will open and display the system’s macOS version.
'Legacy' DisplayLink Driver installation for macOS 10.15 Catalina
We also have a video that demonstrates this process here –> https://youtu.be/ixWKrd5SLKs
Before you begin
If have installed a previous version of the DisplayLink driver, please uninstall it and then reboot your system before proceeding.
1. Download the latest driver for macOS 10.15 Catalina from here -> Link
2. Navigate to your Downloads folder and double-click on the DisplayLink driver download
3, The disk image of the driver will mount, and automatically open the DisplayLink Installer main landing page.
4. Double-click on the ‘DisplayLink Software Installer.pkg’ file. The Install DisplayLink Driver page will open.
*** Depending on your system’s security settings, the installer may not open and instead present you with a warning ***
Click on the ‘OK’ button to dismiss the warning, and then open ‘System Preferences’ (gear icon) and then open the ‘Security & Privacy’ application.
Click on the ‘Open Anyway’ button in the lower right-hand portion of the application window. Then click the ‘Open’ button within the next prompt.
5. Click the ‘Continue’ button shown within the installer’s ‘Introduction’ screen.
6. Click the ‘Agree’ button to accept the license.
7. Click the ‘Install’ button.
8. Click the ‘Continue Installation’ button. The system will need to be restarted when the installation is complete.
9. Enter your system password and click the ‘Install Software’ button.
10. After a few moments, the installer should report a successful installation.
11. The system should also prompt you to access the System Preferences to grant necessary permissions to the DisplayLink driver. Click on the ‘Open System Preferences’ button.
*** If the prompt described above did not appear automatically, manually open the ‘System Preferences’ application (gear icon in the macOS dock at the bottom of the screen) and select the ‘Security & Privacy’ application. Within the ‘Security & Privacy’ application click on the ‘Privacy’ tab. Scroll down in the list of items on the left-hand side of the application window and click to select ‘Screen Recording’. The proceed to the next step ***
12. The ‘Security & Privacy’ application should open and default to showing the ‘Privacy’ tab. On the right-hand side of the application window there should be a single entry entitled, ‘DisplayLinkUserAgent’. Click to place a checkmark next to this entry.
*** Important note – the contents of your screens (displays) are not being recorded. This setting just enables the DisplayLink driver to access the information generated by the system’s built-in graphics adapter to generate the image shown on the DisplayLink-connected displays. ***
13. After having placed a checkmark next to the ‘DisplayLinkUserAgent’ entry, click the ‘Quit Now’ button in the prompt that appears.
14. Close the ‘Security & Privacy’ application, and then restart your system. The DisplayLink device should start working after the restart is complete.
'Legacy' DisplayLink Driver installation for macOS 10.14 Mojave
** Before you begin **
If have installed a previous version of the DisplayLink driver, please uninstall it and then reboot your system before proceeding.
1. Download the latest driver for macOS 10.14 Mojave from here -> Link
2. Navigate to your Downloads folder and double-click on the DisplayLink driver download
3. The disk image of the driver will mount, and automatically open the DisplayLink Installer main landing page
4. Double-click on the ‘DisplayLink Software Installer.pkg’ file. The Install DisplayLink Driver page will open
5. Click ‘Continue’
6. Click the ‘Agree’ button
7. Click ‘Install’
8. Click ‘Continue Installation’ The system will need to be restarted when the installation is complete
9. Enter your system password and click the ‘Install Software’ button
10. There is a chance that the security settings in macOS may block the installation of the DisplayLink extension
11. If that occurs, click on the ‘Open Security Preferences’ button and click the ‘Allow’ button at the bottom of the window to grant permission for the extension to be loaded. ** Important note – this approval must be granted within 30 minutes of the driver installation or the process will not work. A fresh installation must be performed to reset this timer. **
There is also a chance that the warning message about the blocked System Extension will not appear, but macOS may still block the extension. After the driver installation completes, please double-check that the necessary approval was granted by clicking the ‘System Preferences’ icon (the gear) and then clicking on the ‘Security & Privacy’ icon. From the window that appears please ensure the DisplayLink driver is Approved by clicking the ‘Allow’ button.
12. Close the ‘Security and Privacy’ window. The DisplayLink installation should now complete
13. Click on the ‘Restart’ button to restart your system. The DisplayLink device should start working after the restart is complete.
'Legacy' DisplayLink Driver removal for macOS
We also have a video that demonstrates this process here –> https://youtu.be/VRRLJf6D7vc
1. Click the Spotlight magnifying glass icon in the Apple Menu, and search for ‘DisplayLink Software Uninstaller’. Double-click on the result
2. The uninstall window will appear
3. Click the ‘Uninstall’ button
4. Enter your account password and click ‘OK’
5. After a few moments the process will complete. Click the ‘Restart’ button to complete the removal process.
My Windows Laptop Will Not Boot Properly When My Docking Station Is Connected
If your Windows laptop will not boot properly when a DisplayLink-based USB docking station is connected to the laptop, most often the cause is an external device connected to the docking station (for example an external USB storage drive) as opposed to the dock itself.
If you are affected by this condition, please follow these steps in order to isolate the behavior further:
- Disconnect all USB devices from the docking station and put them aside for the moment.
- Disconnect any displays connected to the dock's video outputs.
- Disconnect any audio devices connected to the dock's audio ports (if present).
- Disconnect the Ethernet network cable from the dock's Ethernet port (if present).
- The only remaining connections should be the dock's power adapter cable and the USB cable used to connect it to the laptop. No other external devices should be connected to the dock.
- While in this state, reboot the laptop to test the behavior.
- Assuming the laptop boots as expected, please reconnect each device back to the dock one at a time and reboot after each one to test the behavior again. Please reconnect the displays first, then the audio devices, then the Ethernet cable. Please reconnect any USB devices to the dock last, again rebooting after each one is added to test the behavior.
In our experience helping others, the most common cause of this behavior is an external USB storage drive connected to one of the dock's USB ports. In some cases, a laptop may try to boot from an external storage drive by mistake as opposed to the laptop's built-in storage drive. Since most external USB storage drives are not 'bootable', this can interrupt the boot process.
If this behavior occurs, the most common way to mitigate the behavior is to access the laptop's System BIOS (also known as UEFI firmware) to change the 'boot order' settings to ensure that the laptop's internal storage drive is the first boot option. Doing so helps ensure that the laptop will not try to boot from an external USB storage device.
Every laptop system is different, so the best resource for accessing the System BIOS and changing the settings is the manual for the laptop provided by the laptop manufacturer.
Applications That Use OpenGL Such As Google Sketchup or Google Earth Do Not Work As Expected When Connected to a DisplayLink-Based Docking Station
Docking stations based on DisplayLink USB video technology are in essence a 'virtual' graphics adapter that relies on the host laptop's CPU and internal physical graphics processing unit (aka as GPU) to generate the information shown on the dock-attached displays.
In rare instances, Windows applications that use a technology known as OpenGL to draw the image shown on the display will attempt to direct OpenGL related tasks to the DisplayLink-based docking station's virtual graphics adapter, and not to the 'real'/'physical' GPU within the laptop.
Since the dock is not a physical GPU that supports OpenGL, this can sometimes cause applications that make use of OpenGL (such as Google Earth or AutoCAD) to not work as expected or result in various types of error messages.
The true root cause of this behavior can vary, and ultimately lies outside of the docking station or its associated DisplayLink driver. In some cases the root cause lies within the Windows driver for the host system's physical GPU and in rarer cases within the Windows operating system itself.
In some cases updating either the driver for the system's internal GPU or updating Windows itself (when Microsoft provides such updates) can help, however that is unfortunately not always the case.
If updating those components does not help, in most cases there are two possible workarounds.
The first is to configure Windows to have the ‘Main’ display set to a display directly connected to the host system's built-in internal GPU, whether that is an internal laptop display or another external display connected to one of the system's built-in video outputs (a quick guide to doing so is here -> https://youtu.be/7nnKztRZXsw).
If the first option does not prove a suitable workaround, the second option is to boot the system without the dock connected, launching the affected application, and then connecting the dock may also help.
Why Aren’t My Monitors Working Within macOS After Upgrading to a Newer Version of the DisplayLink Manager Graphics Connectivity App?
When upgrading the DisplayLink Manager Graphics Connectivity App to new version within a macOS system, the update process will cause the older version of the App to quit. As a result, any monitors connected to a DisplayLink-based USB video adapter or docking station will stop working.
The solution is to manually start the new version of the DisplayLink Manager Graphics Connectivity App by double-clicking on the App's icon within the macOS 'Applications' folder within the macOS Finder. This will restart the DisplayLink Manager Graphics Connectivity App, which in turn will enable any monitors connected to a DisplayLink-based USB video adapter or docking station to start working again.
DisplayLink Products Recommended for macOS
This article intends to provide a list of Plugable products that utilize DisplayLink technology that we currently recommend for use with macOS Mojave 10.14 and newer versions of the macOS operating system. For additional information regarding the current limitations with DisplayLink adapters and docks with macOS, please look at our KB article here: https://kb.plugable.com/question/724337
DisplayLink docks that are recommended with USB 3.0 Type-A and USB 3.0 Type-C connection to laptop:
Plugable UD-3900 Dual Display Universal Docking Station (UD-3900)
- USB-C connection achievable with purchase of a separate adapter, USBC-AF3
Plugable USB 3.0 Dual Monitor Horizontal Docking Station (UD-3900H)
Plugable Dual HDMI USB Universal Docking Station For Windows (UD-3900Z)
Plugable Dual 4K Display HDMI or DisplayPort Universal Docking Station (UD-6950Z)
Plugable UD-6950 USB 3.0 Dual DisplayPort 4K Docking Station (UD-6950)
Plugable UD-6950H USB 3.0 Dual 4K Display Horizontal Docking Station with DisplayPort and HDMI (UD-6950H)
DisplayLink docks that are recommended that support USB-C power delivery to the laptop:
Plugable USB-C Triple HDMI Display Docking Station (UD-3900PDZ)
Plugable USB-C Triple 4K Display Docking Station (UD-ULTC4K)
- Note: upon restart of a M1 Mac host system, USB and DisplayLink devices may not reconnect automatically. Please see our article here: https://kb.plugable.com/question/825145
DisplayLink adapters that are recommended:
Plugable USB 3.0 and USB-C 4K DisplayPort and HDMI Dual Monitor Adapter (USBC-6950U)
Plugable USB 3.0 and USB-C 4K DisplayPort and HDMI Dual Monitor Adapter with Ethernet (USBC-6950UE)
DisplayLink docks and adapters that are not compatible or recommended for macOS:
Plugable USB-C Triple Display Docking Station (UD-ULTCDL)