MST is a DisplayPort (DP) 1.2 and newer feature that allows multiple displays to be connected to a single video output. This can be done using a MST hub or by daisy-chaining multiple MST-enabled displays. This technology is driverless, and can be used for seamlessly setting up hotdesking or work from home setups. However, there are some common problems that can occur with these devices.

Display Resolution

While our MST devices can support up to two 4K 60Hz external displays, users of older Intel CPU versions such as the 10th generation Icelake and 11th generation Tigerlake may find that their CPU only supports dual 4K 30Hz, or dual 1080p 60Hz external displays when connected to an MST-based docking station.

Based on internal testing, Plugable expects laptops that support DP 1.4 (Intel 12th gen CPUs or newer) to support up to two 4K 60Hz external displays. Older DP 1.2 hosts typically only support dual 1080p 60Hz external displays.

ARM-based Compatibility

ARM-based systems also do not universally support MST. Whether or not a particular ARM system supports MST depends on the specific SoC (System on a Chip) that is used in the system. Some SoCs such as the Texas Instruments DRA829J do support MST, while others such as the MediaTek MT8127 do not.

If you are unsure whether or not your ARM-based system supports MST, you can check the specifications of your system processor to see if it mentions MST support.

Chart of external display performance for various hosts

Connection issues: (USB-C/Video Cables)

Another potential source of issues are the cables used to connect your dock to your laptop, and your monitors to the dock. 

To connect your dock to your laptop, make sure that you are using a USB-C cable that supports DisplayPort Alt Mode. Plugable recommends using the cable that was provided with your device.

When choosing a video cable for MST, it is important to make sure that the cable supports the desired resolution and refresh rate. To be fully compatible with our MST products, you will want a cable that supports DP 1.4 with a maximum total bandwidth of 32.4Gbps. That gives it enough bandwidth to handle two 4K UHD streams at up to 60Hz. Plugable recommends using the cables that were included with your monitor.

If there are still connection or resolution issues despite using the correct cables, Plugable also recommends swapping out the cables to help determine if the original ones were faulty.

Driver/OS issues: (Staying up to date)

The last major source of compatibility issues with MST-based docks is the operating system your laptop is running. While modern laptops with MST compatible processors that are running operating systems such as Windows 11,10, 8, 7, and ChromeOS do support MST displays and devices, MST is currently not supported by macOS hosts. 

You will also want to make sure that all system and graphics driver updates are applied to avoid any problems with outdated drivers or OS versions.

However, if you have confirmed that all your hardware is compatible and you are still not seeing the expected display results, please feel free to to reach out to our support team as support@plugable.com

For full functionality, the UD-MSTHDC requires at least one of the following ports to be on your laptop:

• Thunderbolt 3 or 4 port
• USB Type-C ports with Alt Mode (DP) and Power Delivery (PD) support

Additionally, the laptop needs to have an Intel 11th gen or newer CPU to support all dock resolutions, as noted below:

• DP 1.4 hosts support up to two 4K 60Hz external displays
• DP 1.2 hosts support up to two 1080p 60Hz external displays

The UD-MSTHDC's power button controls power to the docking station itself, and will not turn on or off the connected host.

The button will be on by default, and can be used to manually turn the dock off, and then back on if needed.

What is MST?

MST stands for Multi-Stream Transport and is based on DisplayPort Technology, allowing multiple uncompressed video streams to be delivered over a single DisplayPort connection (a process known as multiplexing). MST can be used over several different video port mediums, such as DisplayPort, Mini DisplayPort, Thunderbolt 3 or 4, and USB-C ports that support DisplayPort (Alt-Mode).

Two types of connections can be made when using MST. A “daisy-chain” connection where you can link multiple monitors together or an “MST Hub” configuration that can split one DisplayPort cable into multiple video outputs.

For MST to work in a daisy-chain or MST Hub configuration, monitors must support either DisplayPort 1.2 connection (or higher) or Thunderbolt, provide a video “out” port on the monitor, and have MST mode enabled in order for the monitors to work together. Note that HDMI is not supported. 

Daisy-chain example

In many cases, a monitor will not have a video “out” option; this is where an MST Hub will become necessary to break out the video signal to each monitor individually. 

Plugable's USBC-11IN1E shown in this MST Hub example

Will I need additional software to use MST?

MST does not require any additional software and will connect directly to the host GPU in order to bring high-resolution, uncompressed video that is beneficial in a variety of applications such as graphics design and video editing. Resolutions will vary depending on the specifications of the GPU. DisplayPort 1.4 GPUs will support higher resolutions and refresh rates than DisplayPort 1.2, for example. 

It is recommended to use the most up-to-date GPU drivers from your laptop or GPU manufacturer.

Which operating systems support MST?

MST is supported by Windows 11, 10, Windows 8/8.1, Windows 7, and Chrome OS.    
MST is currently not supported by macOS or Mac OS X.

Compatible Plugable MST devices

Now that we have a better idea of MST, Plugable is excited to introduce several MST compatible hubs and docking stations that can help boost productivity and provide external monitor support, including the ability to provide other capabilities such as USB, Ethernet, and even Audio. Some supported products are,  

• USBC-11IN1E
• UD-3900C4
• UD-MSTHDC
• UD-MSTH2

Some of our Thunderbolt supported products include,

• TBT3-UDC3
• TBT3-UDC1
• TBT3-UDZ
• TBT4-UDZ 

Most Windows notebook computers power management settings will default to putting the computer to sleep with the lid closed, regardless of any external displays, keyboard, or mouse connected to the computer. If this is happening but you would prefer the system to remain active with the lid closed utilizing the external display or displays, these settings can be changed by performing the following:

For Windows 10:

1. Start by right-clicking on the Start button and select Power Options from the menu.
2. From the right side of the Power Options settings page, select the blue link for Additional power settings

   

3. From the choices present on the left-hand side of the Power Options window, please click on Choose what closing the lid does
4. Make sure the setting for When I close the lid under the Plugged In column is set to Do Nothing

   

5. 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.

For Windows 11:

1. Start by right-clicking on the Start button and select Power Options from the menu.

   

2. In the upper left corner of the settings window, in the search box, type "lid" then select Change what closing the lid does from the search results

   

3. Make sure the setting for When I close the lid under the Plugged In column is set to Do Nothing

   

4. Click the Save Changes button to apply the new settings.

Closing the lid should no longer put the computer into sleep mode when an external display and power source is connected, instead one of the external displays should now become the Primary display with the desktop icons instead of the laptop's built-in display.

The lid may still need to be opened to perform the following tasks:

• To power on the computer from a fully powered off state
• To log into the computer if logged out or if the computer is restarted with the lid closed
• To wake the computer from a deep sleep state ( hibernation, or Windows hybrid sleep states )

If your Windows laptop will not boot properly when a 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:

1. Disconnect all USB devices from the docking station and put them aside for the moment.
2. Disconnect any displays connected to the dock's video outputs.
3. Disconnect any audio devices connected to the dock's audio ports (if present).
4. Disconnect the Ethernet network cable from the dock's Ethernet port (if present).
5. 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.
6. While in this state, reboot the laptop to test the behavior.
7. 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.   

Below is a list of pre-tested power adapters and corresponding power prongs/cables for Plugable docking stations that can be purchased on eBay if a replacement is needed.

If the power adapter for your docking station or region is not listed or if it out of stock on eBay please contact us at support@plugable.com and we will be happy to assist further.

We offer a 30-day return period for our replacement power adapters listed on eBay.

If your package is missing one or more of the items that should be included with your Plugable dock (included items are listed on a chart on the side of the box), start by double checking if the part is still in the packaging. Pieces can occasionally get stuck in the corners under the main insert in the box.

If you are still unable to locate the piece, please contact support@plugable.com with the following information:

1.  Amazon Order ID (or other proof of purchase) associated with your Plugable device.

2. A description of the parts that are missing from your order.

3. Your preferred shipping address (and a phone number associated with that address).

4. The serial number of your Plugable Dock.

Most Plugable docks do not officially support monitors over 60Hz including 120Hz or 144Hz refresh rate unless otherwise specified on the Plugable product page or listing. 

DisplayLink USB Graphics technology and Silicon Motion based docking stations and graphics adapters, like our USB 3.0 dual display and USB Type-C triple display docking stations, are limited to 60Hz fresh rate by the USB graphics controller hardware.

USB Type-C DisplayPort Alternate Mode docking station and ports on our USB Type-C Triple Display Docking Stations can support higher refresh rates, but may be limited by the computer's capability and available bandwidth to the docking station.  Additionally, when paired with DisplayLink or Silicon Motion USB graphics, having displays at different refresh rates may reduce overall system performance.  Due to this we normally recommend limiting all connected displays to 60Hz refresh rate when using DisplayLink and Silicon Motion graphics technology with directly connected, or USB Type-C DisplayPort Alternate Mode controlled displays.

Monitors with refresh rates higher then 60Hz may be connected to a docking station operating at up to 60Hz, or connected directly on the computer's HDMI or DisplayPort to ensure the display is powered by the system's native GPU.

Unfortunately Plugable products do not support the Apple SuperDrive.

The Apple SuperDrive has stringent power requirements that can only be met by directly connecting the SuperDrive to your host laptop. As a result at this time Apple recommends only using their USB-C adapter cables. You can find more information on that here → How to connect the Apple USB SuperDrive

If you have purchased a Plugable product to use with your Apple SuperDrive, and would like some additional assistance please do not hesitate to reach out. You can do so by emailing support@plugable.com, or going to Plugable.com/Support.

Please Note

The below guide is an advanced troubleshooting step, and we do not recommend doing so unless you are comfortable manually altering files on your Apple product running macOS. You may not be able to perform the below troubleshooting step if you are unable to execute administrative credentials on your laptop. Please reach out to our support first if you do not wish to attempt the below instructions. You can do so at Plugable.com/Support

How to delete a specific Ethernet adapter from your Network devices on macOS

1. Click on the Apple logo in the top left corner of your primary monitor, and select ‘System Preferences’
2. Next select ‘Network’ in the ‘System Preferences' window.
3. In the now visible list, please select the Plugable Ethernet, or Thunderbolt Ethernet device that may not be working as expected.
4. Once selected click on the minus button in the bottom left of the network window.
5. Click on Apply in the bottom right.
6. Next click on the plus button in the bottom left of the network window, and add the previously removed device.
7. Click on Apply in the bottom right.
8. Test to see if this has resolved the unexpected behavior, and assure that your Ethernet is now working.
9. If this does not resolve the problem, please proceed to the next section (As noted previously the next section is for advanced users only!)

I am still unable to get my Ethernet connection working on my Mac

If this is the case please reach out to our support team. When you do please include a diagnostic log gathered using our PlugDebug tool (instructions are provided on the PlugDebug page). If you are not able to gather the PlugDebug diagnostics do not worry we are still here to help! Please reach out to our support team at support@plugable.com or Plugable.com/Support with a detailed description of your problem, and the model of Plugable product you are using.

We are often asked if it is okay to leave a notebook computer connected to one of our USB-C docking stations with Power Delivery for extended periods of time.  The short answer is yes, it is no different from leaving the laptop connected to the manufacturer's original USB-C power supply for the same time.  The long answer is yes for modern laptops, and maybe for older (1990s-early 2000s laptops) and involves going into the different battery technologies used in consumer electronics devices.

Another common question is if it is possible to use the docking station but to disable powering and charging the computer.  When a modern notebook computer runs on battery power it will often set the system to a reduced power state which may impact performance, or connected devices and we recommend always powering the computer when using a desktop docking station.  For all of our docking stations that provide power to the host computer this will not affect the lifespan of the computer's battery.

Modern Laptop Batteries: Lithium-Ion

Lithium-ion (li-ion) batteries are found in a wide range of consumer electronics from notebook computers and cell phones, to electric cars, power tools, and wearable electronics like wireless earbuds.  Li-ion offers fast charging, high-current discharging, fairly long service live compared to other rechargeable battery technologies and are relatively inexpensive.

The life-span of a rechargeable battery depends on many factors including age, temperature history, charging patterns, the chemical composition of the specific battery, and usage.  For example batteries stored at 100% charge will degrade faster than batteries stored at 50% charge, this is why most consumer electronics devices arrive from the manufacturer with between 25% to 75% charge.

Lithium-ion batteries are consumable components, however in most modern computers, cell phones, and tablets these are not user serviceable components.  To help maintain the battery all modern computers and most consumer electronics will include battery charge and protection circuits.  These can be fairly simple, charging up the battery at preset rates depending on the charge level to help maintain the battery life, or complex software controlled charging that monitors battery temperature, voltage and current draw to maintain the fastest charging while maintaining the battery longevity.

Modern notebook computers can be left connected to the original power cable or a docking station with charging capability for extended periods, and do not benefit from regular discharge/recharge cycles.  Our docking stations with charging capability rely on USB Type-C Power Delivery to power and charge compatible computers.  USB Type-C Power Delivery is a negotiated charging protocol between the host computer and the docking station or USB Type-C power supply, this allows the computer to draw only the power it requires, and even select the best voltage level for powering the computer.  In combination with a computer's built-in battery charging controller the computer is capable of maintaining the battery's optimal state even when left connected to a power source for an extended period of time.

Legacy Laptop Batteries: NiCad and NiMH

Older laptops, from the 1990s and some early 2000s, as well as some consumer electronics, and most rechargeable AA or AAA battery replacements use Nickel-Cadmium (NiCad) or Nickel-Metal Hydride (NiMH) batteries.  These batteries are slower to charge and discharge than li-ion batteries, and require very simple charge controllers, and in some cases can even be trickle-charged ( very low-current continuous charging ) if desired.

These batteries generally don't have smart charging controllers and to prolong the life of the battery required "training" or fully discharging and recharging the battery every so often.  Many laptop manufacturers recommended fully charging and discharging a new laptop 2-3 times to train the battery, this is not necessary with modern laptops.

Conclusion

Modern notebook batteries are managed by the computer's built-in battery charging circuit, and require little to no user intervention to maintain optimal battery health.  It does not harm the battery to leave the computer connected to an external power supply, so long as the computer is being used regularly.  If the computer is to be stored for a prolonged period then discharging the battery to between 50-75% can help to maintain the battery life.

Batteries are consumable components and degrade over time, however modern notebook computers can extend the battery life generally to meet or exceed the life of the computer's other electronic components.

It's not uncommon for users to notice a certain level of heat generation from electronics and by extension, Plugable products during operation. In this knowledge base article, we'll explore the reasons behind this heat generation and why it is considered a normal experience within reasonable limits.

Electronics, by their nature, generate heat during operation. This is primarily a result of the electrical current flowing through various components, such as integrated circuits, transistors, and other electronic elements. As Plugable products are designed to efficiently process and transfer data (among other functionality), some level of heat generation is inherent.

Factors Influencing Heat Generation:

1. Power Consumption: The power consumption of a device directly influences the amount of heat it generates. Higher power usage, especially during data transfer or charging processes, can lead to increased heat.
2. Enclosure Design: The design of the product's enclosure and its ability to dissipate heat play a crucial role. Adequate ventilation and heat sinks are often incorporated to manage and disperse generated heat effectively. This is evident in our TBT3-UDZ and TBT4-UDZ designs. The metal case in these docks are designed to function as a heatsink with thermal pads placed throughout the enclosure. This allows heat dissipation from inside to the outside, but will also make it feel as if the device is “too hot”. 
3. Ambient Temperature: The external environment may also play a role. Higher ambient temperatures can contribute to increased perceived heat from the product. This means that summer temperatures may increase the heat generation of not just Plugable products, but many other electronic devices.

Normal Heat Levels: While it is normal for electronic devices to generate heat, Plugable products are engineered to operate within safe temperature ranges. We conduct rigorous testing to ensure that the heat generated during normal operation falls within industry-standard safety parameters. While not all products are or need to be UL certified, we try to go by UL guidelines for thermal readings. The UL threshold is 77C/170.6F, and we aim for around 71C/160F.

Tips for Users:

1. Ventilation: Ensure that Plugable products have sufficient ventilation around them. Avoid placing them in enclosed spaces where heat dissipation may be impeded.
2. Usage Patterns: Intensive tasks such as high-speed data transfer or charging multiple devices simultaneously may result in increased heat generation. This is generally normal but may be more noticeable in such scenarios.
3. Accessories: A number of our devices will allow for the connection of USB accessories and as such, these will require power. If too many “power-hungry” devices are connected, this will cause the device to run much hotter than expected. Be sure to keep in mind the power limits of your dock/device.

In conclusion, experiencing heat from Plugable products is a normal aspect of their operation. Users can rest assured that we prioritize the safety and efficiency of our devices. By understanding the factors influencing heat generation and following simple usage guidelines, users can make the most of their Plugable products while ensuring a reliable and efficient user experience.