Plugable USB-C to HDMI Adapter for Triple Monitors (Windows Only)

Summary

The USBC-MSTH3 is a driverless USB-C to triple HDMI MST video adapter. If one, two, or all three connected displays are not working as expected, the most important items to check are the host computer's USB-C video capability, MST support, DisplayPort version, DSC support, operating system display mode, graphics driver version, HDMI cable rating, and monitor compatibility.

The adapter does not require Plugable drivers or DisplayLink software. It uses the host computer's built-in graphics hardware through USB-C DisplayPort Alternate Mode, USB4, or Thunderbolt video output.

Applicable To

• Plugable USB-C to Triple HDMI MST Video Adapter (USBC-MSTH3)
• Windows 10 or newer and ChromeOS 100 or newer
• USB-C, USB4, Thunderbolt 3, or Thunderbolt 4 host ports that support video output and MST
• Up to three HDMI displays connected through the adapter

Answer

Start by confirming that the computer, display settings, HDMI cables, and monitors meet the requirements for the USBC-MSTH3.

The USBC-MSTH3 must be connected to a USB-C, USB4, or Thunderbolt port that supports DisplayPort Alt Mode or equivalent video output. For multiple independent extended displays, the host system must also support Multi-Stream Transport (MST). If the host system does not support USB-C video output, the adapter will not provide video.

On Windows and ChromeOS, make sure the displays are set to extend rather than mirror. On macOS, multiple independent extended displays are not supported with this adapter because macOS does not support MST through standard MST hubs. Linux is also not officially recommended because MST behavior can vary by distribution, graphics stack, and driver support.

Driver and System Update Checks

The USBC-MSTH3 is plug-and-play on compatible Windows and Chrome OS systems. No Plugable driver is required.

Even though the adapter is driverless, display behavior can still depend on the host system's graphics drivers, firmware, and operating system updates. For best results:

• Run Windows Update or ChromeOS updates
• Install the latest graphics driver from the computer manufacturer or GPU manufacturer
• For Windows systems, check Intel, AMD, or NVIDIA graphics driver updates as appropriate
• Install BIOS, firmware, USB4, or Thunderbolt firmware updates from the computer manufacturer if external display issues continue
• Restart the computer after installing updates

Graphics driver and firmware updates can help resolve missing displays, lower-than-expected resolution options, flickering, blank screens, or displays that mirror when they should extend.

Connection Checks

Check the physical connection path before troubleshooting software settings.

• Connect the USBC-MSTH3 directly to the computer
• Avoid connecting through another dock, hub, extension cable, or USB-C adapter during testing
• Make sure the adapter's built-in USB-C cable is fully inserted
• Connect each monitor directly to the adapter with an HDMI cable
• Use HDMI cables rated for the resolution and refresh rate you want to use
• Confirm each monitor is set to the correct HDMI input
• Test each monitor and HDMI cable individually if only one or two displays are working

The USBC-MSTH3 is a video-only adapter. It does not charge the connected laptop, provide USB data ports, or provide Ethernet.

Display Mode Settings

On Windows:

1. Open Settings.
2. Go to System > Display.
3. Select Detect if one or more displays are missing.
4. Under Multiple displays, choose Extend these displays.
5. Select each display and confirm the resolution, refresh rate, and display arrangement.

On ChromeOS:

1. Open Settings.
2. Go to Device > Displays.
3. Disable mirroring if it is enabled.
4. Arrange the displays as needed.
5. Confirm the resolution and refresh rate for each display.

If the displays are mirrored on Windows or ChromeOS, the system display settings may need to be changed. If the displays are mirrored on macOS, that is expected behavior for this MST adapter.

Host System Requirements

The USBC-MSTH3 depends on the video capabilities of the host computer. The host port must support USB-C video output through one of the following:

• USB-C with DisplayPort Alternate Mode
• USB4 with DisplayPort support
• Thunderbolt 3 or Thunderbolt 4

A data-only USB-C port is not compatible.

For multiple independent external displays, the host system must also support MST. The host system's GPU must also be capable of driving the number of active displays you want to use.

On some laptops, the built-in display counts toward the total number of supported displays. If only two of three external monitors are detected, try closing the laptop lid or disabling the internal display, if supported by the computer manufacturer.

If a simple USB-C to HDMI adapter does not work with the computer’s USB-C port, the USBC-MSTH3 will likely not work either.

Expected Resolution by Host Capability

The USBC-MSTH3 does not create additional video bandwidth. It divides the video bandwidth provided by the host computer across the connected HDMI displays. Because of this, the maximum display configuration depends on the host system's DisplayPort version, MST support, DSC support, and available bandwidth.

Display Stream Compression (DSC) is a display technology that allows higher resolutions and refresh rates to fit within the available DisplayPort bandwidth. For triple 4K 60Hz, DisplayPort 1.4 with DSC or DisplayPort 2.1 is recommended.

Monitor and HDMI Cable Requirements

The monitors and HDMI cables must also support the desired resolution and refresh rate. For example:

• For triple 4K 60Hz, use HDMI 2.0 or newer monitors and HDMI cables rated for HDMI 2.0 or higher
• For dual 4K 144Hz, use HDMI 2.1 monitors and HDMI cables rated for HDMI 2.1
• For a single 8K 60Hz display, use an HDMI 2.1 monitor and HDMI cable rated for HDMI 2.1

Older, damaged, or lower-spec HDMI cables can cause lower available resolutions, lower refresh rates, flickering, blank displays, or unstable display detection.

macOS, Linux, and Mobile Device Expectations

The USBC-MSTH3 is designed primarily for supported Windows and ChromeOS systems.

macOS and iPadOS do not support MST in the same way as Windows and ChromeOS. Because of this:

• macOS is not recommended for multiple extended displays with the USBC-MSTH3
• A Mac may show mirrored displays instead of separate extended displays
• iPadOS supports only one external display
• Many phones and tablets do not support multiple independent external displays through MST adapters

Linux can support MST in some configurations, but results vary by distribution, graphics stack, kernel version, and driver support. Plugable does not officially recommend Linux for the USBC-MSTH3.

For Mac users who need multiple extended displays, a DisplayLink-based adapter or docking station may be a better fit, though those products require driver installation.

Common Symptoms and What They Usually Mean

Need Assistance?

If the USBC-MSTH3 is still not working as expected after checking the items above, contact Plugable Support at support@plugable.com. Please include the computer model, operating system version, graphics adapter, monitor models, HDMI cable type if known, how many displays are connected, and a description of what each display is doing.

Multi-Stream Transport (MST) allows a single USB-C, USB4, or Thunderbolt port to drive multiple independent external monitors. This technology is driverless and can be used to seamlessly set up hotdesking or work-from-home environments. While MST is a standard feature on Windows and ChromeOS, hardware limits still apply. Even if a dock has four ports, your laptop’s internal graphics card (GPU) may only be able to drive two or three displays total.

1. Compatibility

Mac Users: To extend displays on Apple Silicon, use a DisplayLink dock or a Thunderbolt dock (for Pro/Max/M4/M5 chips).

2. Check Your Hardware’s "Display Limit."

Before buying an MST hub or dock for 2, 3 or 4 monitors, you must verify how many displays your laptop's GPU can handle. Note: The laptop’s built-in screen usually counts as one display.

• Intel Iris Xe / Core Ultra: Generally supports up to 4 displays total (e.g., the laptop screen + 3 external monitors).
• Entry-level AMD/Intel (Celeron/Athlon): May be limited to only 2 displays total (laptop screen + 1 external).
• Snapdragon X Elite: Generally supports up to 4 displays total (e.g., the laptop screen + 3 external monitors).
  • ARM Compatibility varies by the specific chip.
  • Some SoCs, such as the Texas Instruments DRA829J, do support MST, while others, such as the MediaTek MT8127, do not. Always check your SoC's technical datasheet for "DisplayPort MST" support.

Tip: If you want to use 3 external monitors and your laptop is limited to 3 total displays, you may need to close the laptop lid to "disable" the internal screen and free up a display slot for the third external monitor.

3. Plugable MST & Hybrid Product Guide

Important Note on the UD-3900C4: This is a "Hybrid" dock. HDMI ports 1 and 2 use DisplayLink (drivers required) and do not count toward your GPU's MST limit. HDMI ports 3 and 4 do use MST and require your laptop's hardware support.

4. Bandwidth: The "Pipe" Problem

Think of your USB-C port as a water pipe. MST splits that pipe. If you try to push three 4K signals through a small pipe (older DP 1.2), the screens can flicker, disconnect or drop to low resolution. It is essential to use certified, high-quality cables to ensure stable and full-bandwidth video transmission.

Maximum Performance Matrix

5. Troubleshooting and FAQ

• "Only one or two of the connected monitors are functioning.": Try closing your laptop lid. If the second or third monitor powers on, you have reached your GPU's maximum display count.
• "The 4th monitor on my UD-3900C4 is mirroring.": This means your laptop likely does not support MST, or you are on an Apple system.
• "I have a Mac, and it's mirroring.": This is the expected behaviour, as Apple does not support Multi-Stream Transport (MST).
• For base Apple Silicon models, you must use DisplayLink technology to overcome limitations of external displays. However, if you have an M4, M5, or a Pro/Max version of Apple silicon, a Thunderbolt docking station can also be used to extend your displays.

5.1 Connection Issues: USB-C & Video Cables

The cables you use are just as important as the dock itself. High-resolution multi-monitor setups require high bandwidth.

• Always use the USB-C cable that was provided with your Plugable dock. This cable is specifically rated to support DisplayPort Alt Mode and the dock's power delivery requirements.
• For best results, use cables that support DP 1.4+ with a maximum bandwidth of 32.4 Gbps. This provides enough room for two 4K UHD streams at 60Hz.
• Use the cables included with your monitors. If you experience flickering or lower-than-expected resolution, try swapping the cables to rule out a faulty or low-bandwidth cable.

5.2 Driver & OS Maintenance

To ensure a stable connection, your software must be up to date with your hardware.

• Ensure Windows or ChromeOS is fully up to date.
• Outdated Intel, NVIDIA, or AMD drivers are a common cause of MST failure. Visit your laptop manufacturer’s website to download the latest graphics drivers.
• If a monitor isn't detected, try a "Power Cycle": Unplug the dock from the laptop, power it off, wait 30 seconds, then reconnect.

Still Unsure?

Email support@plugable.com with your laptop's model number and the monitors you plan to use and we will do our best to determine if an MST solution is right for you. 

This display adapter draws power from the USB-C port that it is connected to in order to function. So there is no need for an external power supply to operate this device but it is recommended to keep in mind that this will draw power from your computer.

This device does not include any extra cables, but it does have a built-in USB-C cable for connecting to the host computer. For connecting displays, you will want to use a set of HDMI cables.

This display adapter requires a connection that supports USB-C DisplayPort Alt Mode for extending the displays. The use of any adapter to convert a USB-C signal to USB Type-A would not have the capability of supporting display extensions. As such, this device would not function for extending displays when used in such a manner.

If your computer does not have a USB-C port, you may want to look into our USB 3.0 display adapters such as the following, which should be compatible:

• Plugable USB-C or USB 3.0 to Dual HDMI Adapter
• Plugable USB 3.0 and USB-C 4K DisplayPort and HDMI Dual Monitor Adapter

Note that each of these devices do require driver installation.

When you connect this directly to a MacBook, you will only see mirrored content on both screens. This is because macOS and iPadOS are not designed to support Multi-Stream Transport (MST) which the Plugable USBC-MSTH2 and USBC-MSTH3 video adapters rely on to power two displays.

The USBC-MSTH2 will only work with a USB-C port or Thunderbolt port that supports DisplayPort Alt Mode for extending external displays.

If your computer does not support DisplayPort Alt Mode, you may want to look into our USB 3.0 display adapters such as the following, which should be compatible:

• Plugable USB-C or USB 3.0 to Dual HDMI Adapter
• Plugable USB 3.0 and USB-C 4K DisplayPort and HDMI Dual Monitor Adapter

Note that each of these devices do require driver installation.

Windows defaults to putting the computer to sleep when the lid is closed, even if there are external displays and devices connected, we can change this setting to enable closing the lid while using a docking station.

Recommended Setup

To ensure the computer can reliably function with the lid closed there are some requirements and recommendations:

1. The system should be powered: This can be from a USB Type-C Docking Station with host charging, or by connecting the laptop's original power source.
2. There should be at least one external display connected, this can be through a docking station, or directly to the computer.
3. There should be a keyboard and mouse connected, either through a docking station, USB Hub, or directly to the computer.

Windows 11 24H2 and Newer

1. Right-click on the Start menu and select Power Options from the context menu

   

2. Expand the Lid, power & sleep button controls sub-section

   

3. Under Plugged in select Do Nothing from the Closing the lid will make my PC  context menu

Windows 11 23H2 and Earlier

1. Right-click on the Start menu and select Power Options from the context 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.

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.

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.

When to open the lid?

The laptop lid may still need to be opened when performing any of the following:

• 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 you have any questions please feel free to contact us at support@plugable.com and we'll be happy to help!

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.

Many modern displays can support above the default 60Hz refresh rate, however this may need to be manually set within Windows 11. Please note, not all computers, graphics adapters, and docking stations can support all resolutions and refresh rates.

Setting the Display Refresh Rate in Windows 11

1. Right-click on the desktop and select Display Settings from the drop-down menu

2. Scroll down to the Related settings subsection and select Advanced display

3. At the top of the Advanced display window, select the external display from the drop-down menu

4. From the Choose a refresh rate drop-down menu select the desired refresh rate

Refresh Rate Limitations

With Windows 24H2 and newer, dynamic refresh rates are supported, this allows the system to adjust the display refresh rate to save power, up to the selected refresh rate. As a consequence of this new mode, when selecting the display refresh rate you may see an asterisk. This indicates that selecting the specific refresh rate may reduce the display resolution or image quality in order to prioritize the refresh rate. This exposes the refresh rate option from the display even if the display cable or computer is incapable of supporting that refresh rate at the native resolution and is the intended behavior per Microsoft. [1]

In the screenshot below the left side shows the 4K 120Hz capable display limited to 60Hz refresh rate without asterisks, and on the right the same display after setting the refresh rate to “120 Hz*”, the “Desktop mode” resolution has been reduced to 2560 x 1440 (1440p) instead of 3840 x 2160 (4K UHD). Unlike when using the display scaling option this also causes a reduction in image quality. On the right side asterisks are no longer shown in the refresh rate list. Setting the refresh rate back to 60Hz does not change the resolution, you will have to go back one page and set the resolution manually.

References

[1] Windows Insider description of new behavior (https://blogs.windows.com/windows-insider/2023/08/31/announcing-windows-11-insider-preview-build-25941-canary-channel/)

At first glance, USB-C and Thunderbolt ports may look the same, but their capabilities can vary significantly. Understanding these differences is key to ensuring compatibility and getting the most out of your Plugable devices.

What is USB-C?

USB-C is a type of connector that supports a range of protocols including data transfer, video output, and charging. It's widely adopted across modern laptops, smartphones, tablets, and more.

Common USB-C Standards:

• USB 3.0 / 3.1 Gen 1: Up to 5Gbps data transfer.
• USB 3.2 Gen 2: Up to 10Gbps data transfer.
• USB 3.2 Gen 2x2: Up to 20Gbps data transfer.
• USB4: Up to 40Gbps data transfer, supports DisplayPort 1.4 and optional Thunderbolt 3 compatibility.

Note: USB-C ports may or may not support features like video output (DisplayPort Alt Mode) or USB Power Delivery (PD). Always check your device's specs.

What is Thunderbolt?

Thunderbolt is a hardware interface developed by Intel (in collaboration with Apple for earlier versions) that builds on USB-C, but adds advanced features and higher performance.

Thunderbolt Versions:

Thunderbolt 3:

• Up to 40Gbps data transfer
• Supports two 4K displays or one 5K display
• Supports USB, DisplayPort, and PCIe over a single cable
• Provides up to 100w of Power Delivery (PD)

Thunderbolt 4:

• Maintains Thunderbolt 3's speeds (40Gbps)
• Support for dual 4K or one 8K display
• Can be used with USB4 ports
• Provides up to 100w of PD

Thunderbolt 5:

• Up to 80Gbps bi-directional bandwidth, and up to 120Gbps in one direction for high-bandwidth applications (using Bandwidth Boost)
• Supports dual 6K displays or a single high-refresh-rate 8K display
• Backward compatible with Thunderbolt 4 and USB4
• Enhanced PCIe support and improved power efficiency
• Ideal for advanced gaming setups, content creation, and future-proof professional workflows

USB-C vs. Thunderbolt: Key Differences

How to Identify Each Port

• Thunderbolt ports often have a lightning bolt symbol next to the port.
• USB-C ports may be unmarked or show a symbol for power or DisplayPort.
• Refer to your laptop or device’s technical specifications for confirmation.

Compatibility Tips

• Thunderbolt 3/4/5 devices can typically connect to USB-C ports, but they will function at reduced capabilities (e.g., lower speeds, fewer display outputs).
• USB-C devices can connect to Thunderbolt ports and work normally, but won’t take advantage of Thunderbolt’s full capabilities.

Understanding whether your device supports USB-C, Thunderbolt, or both can help you choose the right Plugable docking station or adapter for your needs. If you run into any questions, feel free to reach out to our support team at support@plugable.com

Many users assume that USB-C devices can work with older Thunderbolt 2 Macs if they use a Thunderbolt 3 to Thunderbolt 2 adapter, such as the one made by Apple. However, this is not the case. These adapters are specifically designed to support Thunderbolt devices only - not standard USB-C peripherals.

While Thunderbolt 3 and USB-C share the same connector type, they use different underlying data protocols. Non-Thunderbolt USB-C devices, rely on USB standards for data and power. The Thunderbolt 3 to Thunderbolt 2 adapter does not carry USB signals; it only passes Thunderbolt data. Because of this, plugging a USB-C device into a Thunderbolt 2 Mac using this adapter will not work - the computer will not detect or communicate with the device.

If you need to connect peripherals to a Thunderbolt 2 system, we recommend using a USB-A dock or hub (if available on your system). This ensures compatibility without relying on unsupported adapter chains.

In short, even though the connectors may fit, USB-C devices are not compatible with Thunderbolt 2 Macs via Thunderbolt adapters - only Thunderbolt devices will work in that setup.

The Plugable USBC-MSTH3 is a USB-C to triple HDMI video adapter that uses DisplayPort Alternate Mode with Multi-Stream Transport (MST) to drive up to three displays from one compatible USB-C, USB4, or Thunderbolt port.

The adapter is designed for compatible Windows 10 or newer and ChromeOS 100 or newer systems. It does not require DisplayLink drivers or other software installation. It uses the host computer's built-in graphics capability, so the maximum number of displays, resolution, and refresh rate depend on the host system's USB-C video support, DisplayPort version, MST support, and available display bandwidth. Plugable lists the USBC-MSTH3 as supporting Windows 10 or newer and ChromeOS 100 or newer on systems with a USB-C, USB4, or Thunderbolt port with video output. Plugable also notes that maximum resolution and refresh rate depend on the host system's video capabilities.

Display Configuration Capabilities

The number and resolution of displays supported depend on the host system's DisplayPort version, MST support, DSC support, and available bandwidth. The connected monitors and HDMI cables must also support the desired resolution and refresh rate.

Note: One HDMI display up to 8K 60Hz, two HDMI displays up to 4K 144Hz, or three HDMI displays up to 4K 60Hz, with maximum resolution and refresh rate dependent on the host system's video capabilities.

System Requirements

To use the USBC-MSTH3, the host system must support USB-C video output through one of the following:

• USB-C with DisplayPort Alternate Mode
• USB4 with DisplayPort support
• Thunderbolt 3 or Thunderbolt 4

A data-only USB-C port is not compatible. 

The host system must also support MST for multiple independent extended displays. If a simple USB-C to HDMI adapter does not work with the computer, the USBC-MSTH3 will likely not work either.

Full Compatibility

DisplayPort 2.1
DisplayPort 2.1 systems can support the highest display configurations available through the USBC-MSTH3, including up to one 8K 60Hz display, dual 4K 144Hz displays, or triple 4K 60Hz displays, assuming the monitors and HDMI cables also meet the required specifications.

Limited Compatibility

DisplayPort 1.4 with Display Stream Compression (DSC) - DisplayPort 1.4 systems with DSC can support higher-resolution configurations by using compression. Plugable lists DisplayPort 1.4 with DSC as supporting up to 8K 30Hz, dual 4K 120Hz, or triple 4K 60Hz.

DisplayPort 1.4 without DSC - DisplayPort 1.4 systems without DSC are more limited by available bandwidth. These systems may be limited to dual 4K 60Hz or triple 1080p 60Hz.

Basic Compatibility

DisplayPort 1.2 - DisplayPort 1.2 systems have significantly less available display bandwidth. These systems may be limited to dual 1080p 60Hz or single 4K 30Hz and are not recommended for triple-display use. DisplayPort 1.2 hosts support dual 1080p 60Hz or single 4K 30Hz. Not recommended for triple-display use.

Operating System Compatibility

macOS Note - The USBC-MSTH3 is not recommended for Mac systems. macOS does not support MST for multiple independent extended displays through standard MST adapters. On a Mac, connected displays may mirror instead of extend. Mac systems do not support MST and will only support mirrored displays, not extended or independent displays, with the USBC-MSTH3.

Monitor and Cable Requirements

The host computer is only one part of the display chain. The monitors and HDMI cables must also support the resolution and refresh rate you want to use.

• For 4K 60Hz, use monitors that support HDMI 2.0 and HDMI cables rated for HDMI 2.0.
• For 8K 60Hz, use a monitor that supports HDMI 2.1 and an HDMI cable rated for HDMI 2.1.

Using older, damaged, or lower-spec HDMI cables can result in lower available resolutions, lower refresh rates, flickering, blank displays, or unstable display detection. Plugable notes that 4K 60Hz requires HDMI 2.0 monitors and certified HDMI 2.0 cables, while 8K 60Hz requires HDMI 2.1 monitors and certified HDMI 2.1 cables.

Important Notes:

• The USBC-MSTH3 is a video-only adapter.
• It does not charge the connected laptop.
• It does not provide USB data ports.
• It does not provide Ethernet.
• It does not use DisplayLink technology.
• It does not require DisplayLink drivers.

It uses the host computer's built-in graphics through USB-C DisplayPort Alternate Mode, USB4 with DisplayPort support, or Thunderbolt video output.

Before You Buy Checklist

• The computer runs Windows 10 or newer, Windows 11, or ChromeOS 100 or newer
• The USB-C, USB4, or Thunderbolt port supports video output
• The system supports MST
• The system's DisplayPort version is known
• DSC support is confirmed if triple 4K 60Hz is needed
• The monitors support the desired resolution and refresh rate
• The HDMI cables support the desired resolution and refresh rate
• The user needs extended displays, not mirrored displays
• The system is not a Mac if multiple independent extended displays are required

FAQ

Q: Can I use the USBC-MSTH3 with a MacBook?

A: The USBC-MSTH3 is not recommended for Mac systems. macOS does not support MST for multiple independent extended displays through this type of adapter. Displays may mirror instead of extend.

Q: Will the USBC-MSTH3 charge my laptop?

A: No. The USBC-MSTH3 is a video-only adapter and does not support USB-C Power Delivery pass-through charging.

Q: Does the USBC-MSTH3 require drivers?

A: No. The USBC-MSTH3 is plug and play on compatible Windows and ChromeOS systems. Updated graphics drivers and operating system updates are recommended for best results.

Q: How do I know if my system supports MST?

A: Check the computer manufacturer's specifications for USB-C DisplayPort Alternate Mode, USB4 with DisplayPort support, or Thunderbolt 3/4 support. You may also need to confirm the system's DisplayPort version and whether DSC is supported.

Q: What happens if my system does not support enough display bandwidth?

A: The system may limit the available resolutions, refresh rates, or number of active displays. For example, a lower-bandwidth system may support dual 1080p displays or one 4K display, but not triple 4K 60Hz.

Q: Why does one laptop support triple 4K 60Hz while another does not?

A: The USBC-MSTH3 depends on the host computer's graphics capability, USB-C video support, DisplayPort version, MST support, and DSC support. Two laptops can have the same USB-C connector shape but very different video capabilities.

Still Need Help?

If you have any questions or need help determining compatibility with your system, please reach out to our support team at support@plugable.com.

Up to date graphics drivers are necessary for ensuring the best performance of your computer's built-in display, as well as the capability and compatibility with external displays and docking stations.

Windows has a built-in system update service: Windows Update, however this may not provide up to date drivers or timely updates. We often see systems with out of date drivers, in some cases systems may not receive updated graphics drivers for months or even years, leaving the computer with drivers incompatible with the installed version of Windows 11.

However, we can manually update the graphics drivers to ensure the best possible performance, reliability, and compatibility.

The first step is to identify the graphics hardware, then downloading, and installing the latest drivers.

Identifying Graphics Controller

For notebooks and many desktop computers, the primary graphics controller is embedded in the processor, both AMD and Intel provide graphics driver updates based on the processor model, as well as for discrete graphics controllers. Our first step is to identify up the processor or graphics hardware model details:

1. Right-click on the Start Menu and select Settings from the pop-up menu
2. From the left column select System and from the bottom of the right side select About
3. From the top of the about page the processor details will be on the right side, and duplicated lower down on the page.
   
4. In this example the processor is a 12th Gen Intel(R) Core(TM) i7-1260P, we'll keep that detail for the next step.

If your computer has two graphics controllers (it may show "Multiple GPUs Installed" under Graphics Card) then we can get the graphics card model details from the Windows System Information Utility.

1. Open the Start menu and search for "msinfo32"
2. Select the first result
3. From the left-column expand the Components section, then select Display
   
4. In this example the Intel Iris(R) Xe Graphics is enabled by the processor, while the Intel(R) Arc(TM) Pro B60 Graphics is a discrete graphics controller.

Downloading the Drivers

Intel Graphics

1. In a web browser navigate to the Intel Driver Download Page
2. In the "Search Drivers & Software" field, search for the Intel graphics card model or CPU model, "Arc Pro B60" in this example
   
3. Select the appropriate "Intel Arc Pro Graphics - Windows" or similar entry from the search results, for modern hardware Intel will normally have at least one release per month, the list should return recent results within the last month
4. Select the Download button to save the installer to your Downloads folder or selected location

AMD Graphics

AMD provides an Auto-Detect utility, this works relatively well and can be used to update the system available from the AMD Drivers and Support page.

This page also provides a search and browse option for finding drivers and specific compatibility details, we'll look up the drivers for an AMD Ryzen Pro 5650U processor with Radeon Graphics:

1. Navigate to AMD Drivers and Support page
2. From the Browse section, fill out the processor details and click the Submit button
   
3. Expand the "Windows 11 - 64-Bit Edition" section and select the Download button for the latest graphics drivers

NVIDIA Graphics

Like AMD, NVIDIA provides an automatic installation utility, as well as a Manual Driver Search on the NVIDIA Drivers support page. We will look up the drivers for an NVIDIA RTX 5080 graphics card.

1. Navigate to NVIDIA Drivers support page
2. Fill out the Manual Driver Search drop-downs and select the "Find" button when complete
   
3. From the search results, select the "View" button for the GeForce Game Ready Driver or NVIDIA Studio Driver (if you need the studio driver features)
4. Select the green Download button for the latest graphics drivers

Installing the Graphics Drivers

For the most part this is relatively simple, we recommend disconnecting any external docking stations or devices that are not necessary for the driver installation, and for notebook computers connecting the system's original power supply.

Double-click on the downloaded driver installation executable and follow the on screen steps.

For more in-depth details on Intel, AMD, and NVIDIA's driver installation processes check out our step-by-step guides here:

• Intel Driver Installation In Detail
• AMD Driver Installation In Detail
• NVIDIA Driver Installation In Detail

If you have any questions or would like a recommendation, feel free to reach out to our support at support@plugable.com

For a step-by-step guide to identify your graphics hardware and download the appropriate drivers, check out our KB article here

Download the drivers for your GPU or Processor Graphics

1. In a web browser navigate to the Intel Driver Download Page
2. In the Search Drivers & Software field, search for the Intel graphics card model or CPU model, "Arc Pro B60" in this example
3. Select the appropriate Intel Arc Pro Graphics - Windows or similar entry from the search results, for modern hardware Intel will normally have at least one release per month, the list should return recent results within the last month
4. Select the Download button to save the installer to your Downloads folder or selected location

Install the Intel Graphics Driver

To update the Intel Graphics Drivers to the latest version from Intel's website:

1. Save and close any open applications
2. Navigate to the downloaded graphics driver, then right-click on the saved driver installation file and select Run as administrator to start the installation process
3. Allow the Intel driver installation through the User account control window, the drivers will be extracted
   
4. When the extraction is complete select the Begin installation button
   
5. Agree to the Intel Software License Agreement by selecting the I agree button
   
6. Ensure all applications are saved and closed before selecting the I agree button
   
7. For most installations, we recommend not selecting the Execute a clean installation checkbox. This option will remove previous driver versions and can lead to Windows Update reverting to an even older graphics driver. Select the Start button to proceed
   
8. The installation process will proceed, but can take some time to complete
   
9. When the installation has completed, deselect the Launch Intel Graphics Software checkbox - we don't need that right now, select the Reboot Now button to restart the computer applying the new graphics drivers
   

Windows should now detect the Intel Graphics Controller in the Device Manager and show the latest drivers.

If you have any questions or would like a recommendation, feel free to reach out to our support at support@plugable.com

For a step-by-step guide to identify your graphics hardware and download the appropriate drivers, check out our KB article here

Download the drivers for your GPU or Processor Graphics

1. In a web browser navigate to the AMD Drivers and Support page
2. In the Search for your AMD product field, type in the model name, for example “RX 5600XT” for the AMD Radeon RX 5600 XT graphics controller, or a processor model like "AI 9 365", then select the best fitting result and select the Search button - note: Searching for a processor the "™" is required, so I recommend searching for the text after that symbol.
   
3. On the results page, expand the section for Windows 11 64-bit then select the Download button for the latest AMD Software: Adrenalin Edition drivers, AMD may not provide a direct download for all hardware, in that case use the Auto-Detect and Install option
4. Save the installer to your Downloads folder or selected location

Install the AMD Graphics Driver

To update the AMD Graphics Drivers to the latest version from AMD’s website:

1. Save and close any open applications
2. Navigate to the downloaded graphics driver, then right-click on the saved driver installation file and select Run as administrator to start the installation process
3. Allow the Intel driver installation through the User account control window, the drivers will be extracted
   
4. For most users the express installation is fine, ensure all applications are saved and closed selecting the Accept & Express Install button. If you have been having issues with older graphics drivers causing crashes or errors the Factory Reset (Optional) checkbox may be selected, but it isn’t necessary for most installations.
   
5. The installation will proceed, the displays may flicker or flash off/on while the drivers are installing.
   
6. When complete you will be prompted to Launch AMD Software: Adrenalin Edition and Keep AMD software up to date, you can uncheck the Launch AMD Software option
   
7. Restart the computer to ensure the latest drivers are loaded from boot Start Menu > Power Icon > Restart

Windows should now detect the Intel Graphics Controller in the Device Manager and show the latest drivers.

If you have any questions or would like a recommendation, feel free to reach out to our support at support@plugable.com

For a step-by-step guide to identify your graphics hardware and download the appropriate drivers, check out our KB article here

Download the drivers for your GPU

Check your invoice for the specific model of NVIDIA graphics card, for this example we will use the RTX 5080 (the manufacturer is not relevant).

1. In a web browser navigate to the NVIDIA Driver Download Page
2. In the Manual Driver Search field, search for the NVIDIA graphics card model, "RTX 5080" in this example
3. Select the GeForce RTX 50 Series | NVIDIA GeForce RTX 5080 | Windows 11 entry from the list
4. Left-click the Find button
5. Select either View buttons from the GeForce Game Ready Driver or NVIDIA Studio Driver
6. Select the Download button to save the installer to your Downloads folder or selected location

Install the NVIDIA Graphics Driver

To update the NVIDIA Graphics Drivers to the latest version from NVIDIA's website:

1. Save and close any open applications
2. Navigate to the downloaded graphics driver, then right-click on the saved driver installation file and select Run as administrator to start the installation process
3. Allow the NVIDIA driver installation through the User account control window
4. Click OK to extract the NVIDIA Display Driver package contents
   
5. At the System Check step, select either the NVIDIA Graphics Driver with NVIDIA App or the NVIDIA Graphics Driver alone, the NVIDIA App is gaming oriented and unnecessary for most users. Select AGREE AND CONTINUE
   
6. At the License Agreement step, select the Express (Recommended) radio button then select NEXT to continue
   
7. The installation will take some time to complete
   
8. When complete please restart the computer Start > Power > Restart
   

Windows should now detect the NVIDIA Graphics Controller in the Device Manager and show the latest drivers.

If you have any questions or would like a recommendation, feel free to reach out to our support at support@plugable.com

No, target display mode generally requires a direct Thunderbolt connection from a compatible MacBook or Mac Mini to a compatible iMac. Graphics adapters and docking stations do not pass the required Thunderbolt video data.

Why Target Display Mode Is Not Compatible With Docks or Adapters

Target Display Mode is a legacy feature that allows certain older Mac systems to use an older model iMac as an external display via a Mini DisplayPort or Thunderbolt data cable. Most Plugable docking stations and graphics adapters are USB devices that do not meet the specific Thunderbolt data requirements for 2011 through mid-2014 iMac systems. While Thunderbolt 3 or newer docks may provide video capability, they are generally recommended for Apple M-Series systems which do not support this feature.

iMac Models as Display

Apple provides system compatibility here but we can summarize it in the following:

24-inch and 27-inch iMac (2009 and 2010)

• macOS 10.13 “High Sierra” or earlier
• Compatible with Macs from 2019 or earlier with macOS 10.15 “Catalina” or earlier
  • NOTE: some MacBooks in this range do not include a Mini DisplayPort output and may not be compatible
• Connected with a Mini DisplayPort cable

iMac models (2011 through mid-2014)

• macOS 10.13 “High Sierra” or earlier
• Compatible with Macs from 2019 or earlier with macOS 10.15 “Catalina” or earlier
  • NOTE: some MacBooks in this range do not include a Mini DisplayPort output and may not be compatible
• Connected with a Thunderbolt or Thunderbolt 2 cable - these use the Mini DisplayPort connector
  • NOTE: This is not compatible with Thunderbolt 3 (USB Type-C) cables

Alternative Options

For earlier 2009-2010 iMacs, it may be possible to use a USB Type-C to DisplayPort adapter paired with a DisplayPort to Mini DisplayPort cable. However, this configuration is untested and we do not support this configuration.

Our research has shown mixed results using these early model iMac systems with adapters, modern unsupported Apple hosts, or Windows computers. Because Target Display Mode is no longer supported by modern Apple hardware and software, there is no guaranteed workaround for newer systems.

Modern displays offer higher resolutions, multiple connection options: both DisplayPort and HDMI, and newer features like High Dynamic Range (HDR) and higher refresh rates than iMac systems. Many modern displays can support multiple host computers either by switching between inputs or with picture-by-picture or picture-in-picture modes.

Applicable To

• 24-inch and 27-inch iMac (2009 and 2010)
• iMac models (2011 through mid-2014)
• macOS 10.13 “High Sierra” or earlier

If you have any questions please feel free to contact us at support@plugable.com and we'll be happy to help!