Mini DisplayPort to DisplayPort Multi-Monitor Splitter - 3-Port MST Hub

You may have heard of MST hubs, and have been wondering what they are, and whether or not they will work in your setup. 

So what are MST hubs?  MST hubs are devices that take one DisplayPort or Mini DisplayPort video connection, and go to many video connections, usually extra DisplayPort, Mini DisplayPort, DVI or HDMI connections.  This is accomplished through DisplayPort's MST, or Multi Stream Transport function.  MST hubs allow you to mirror / duplicate your monitors so the same window are shown on all of the monitors, or extend your desktop, so that you can have different window on each monitor.

So how can you tell if you can use a MST hub?  MST hubs require that the video card's DisplayPort or Mini DisplayPort output support DP1.2 or greater, which supports MST.  Some MST hubs also specifically require HBR2, or High Bit Rate 2 support.  HBR2 allows for higher resolutions like 4K and up.  You can check whether or not a StarTech.com MST hub requires HBR2 on the individual product pages, under the Technical Specifications tab.

There are a few other important things to note.

• Video cards can technically support DP1.2, but not support MST or HBR2, so it is important to check with your video card manufacturer that your video card specifically supports DP1.2, MST, and HBR2 (if necessary).

Currently Mac OSX does not support MST hubs, regardless of whether or not the video card does.  This is an operating system restriction, so running Windows on an Apple computer through a program like Bootcamp will allow you to use MST hubs.

Recent versions of DisplayPort include the ability to split to multiple displays from one DisplayPort connection using Multi-Stream Transport (MST).

Although you will be able to connect the MST hub to the Mini DisplayPort (mDP) connection on your Mac, Mac OSX does not support MST for NVIDIA and Intel Graphics Processor Units (GPUs). This results in a mirrored image across the outputs of a MST hub and you will not be able to have multiple independent displays on your Mac.

The limitation of NVIDIA and Intel GPUs lies within Mac OSX. If a different operating system is used, such as Microsoft Windows via Bootcamp, you may be able to use the MST functionality of your Mac.

When you convert from DisplayPort to DVI or HDMI, it works best if you use passive video signal converters with StarTech.com MST hubs. The MST hub has the capability to convert a video signal DisplayPort to a DVI or HDMI video signal as long as a video signal converter is used to change the connection type. This is because DisplayPort 1.2 (DP 1.2) supports both MST (Multi-Stream Transport) and Dual Mode (DP++). For more information, refer to the following FAQ: http://www.startech.com/faq/displayport_converter_dp_multi_mode.

When you convert from DisplayPort to VGA, you must use an active adapter because DisplayPort uses a digital signal and VGA uses an analog signal, and the MST hub cannot convert from a digital signal to an analog signal.

Note: When you use a StarTech.com video signal converter to convert from DisplayPort to VGA, you should use the DP2VGA3. In certain circumstances, the DP2VGA2 has compatibility issues with certain VGA monitors.

Surface Dock

If you experience issues when you use a Surface Dock to connect passive video signal adapters to an MST hub, Microsoft recommends that you use active video signal converters instead. StarTech.com offers an active video signal converter for DVI monitors (DP2DVIS) and for HDMI monitors (DP2HD4KS).

Note: This issue does not apply to the Surface Pro 3 Docking Station.

Note: For information about Microsoft Surface tablets and MST, refer to the following FAQ: http://www.startech.com/faq/mst-hubs-microsoft-surface-tablet-compatibility.

Recent versions of DisplayPort include the ability to split to multiple displays from one DisplayPort connection using Multi-Stream Transport (MST).

Although you can connect the MST hub to any DisplayPort (DP) or Mini DisplayPort (mDP) connection, the graphics card in the computer must support MST to use a MST hub.

MST was added for DisplayPort 1.2 and includes support for High Bit Rate 2 (HBR2), which is required to operate MST. However, some manufacturers may not have implemented full support for MST.

If you are unsure if your computer supports MST, try the following:

• Research the technical specifications of the DisplayPort sources for MST.

• If no information is available for your product, contact the manufacturer for assistance.

• Use USB video adapters found on StarTech.com as an alternative method to obtain multiple displays.

On a system with MST compatibility, multiple monitors are detected when they are connected to the hub. Multiple monitors can be used in the following configurations:

• Extended: for separate, independent desktops/displays.

• Spanned: a large, wide resolution that spans or spreads across multiple displays.

• Duplicated: mirrored images on each display.

When a graphics card does not support MST, the hub will duplicate (mirror) the display across all three of the connections. Only one monitor will show in the displays configuration of your system.

You cannot use an MST hub to increase the maximum number of displays that a video card supports. For example, if your video card only supports up to three displays, your display limit will still be three displays even if you use an MST hub.

If you have multiple MST hubs connected to the same computer and are experiencing display issues, you should check your video card to make sure that it can support the number of displays that you are using in your setup.

If you use an MST hub in your setup, your video card also needs to be compatible with MST technology. For more information, refer to the following FAQ: https://www.startech.com/faq/mst-hubs-gpu-compatibility.

Although most Microsoft Surface tablets include Mini DisplayPort, the capabilities vary depending on the tablet model. For more information about MST hub compatibility, refer to the following table:

*The Surface Pro 4 does not work with an MST hub when the Surface Pro 4 is connected to the Surface Dock. If the Surface Pro 4 is directly connected, it will work with an MST hub.

In order to access the full functionality of the hub, you need to install the latest drivers provided by Microsoft Update.

Note: You cannot use an MST hub to increase the maximum number of displays that a video card supports. For example, if your video card only supports up to three displays, (as is the case with all of the Surface models listed above), your display limit will still be three displays even if you use an MST hub.

To set up a MST hub with your MST compatible system, complete the following:

1. Plug the MST hub into a compatible DisplayPort 1.2 output from your computer.
2. Plug the power into the MST hub.
3. Plug your DisplayPort monitors or DisplayPort adapters/converters into the MST hub.
4. Turn on your computer.

You should be able to detect the monitors in the display properties of your operating system.

If you are not getting any additional displays, try the following:

• Verify that the latest display drivers are installed.
• Press and hold the Scan button for five seconds on the MST hub.

When the monitors are detected in the display properties of your operating system, make sure that the resolutions that you are setting do not exceed the total data throughput of the DisplayPort host connection. You can verify the total data throughput (bandwidth) under the Product Overview tab for you device.

Windows 10 / 8

1. On your keyboard, press the Windows Key + X and select Control Panel.
2. Click Appearance and Personalization, then click Display.
3. Click the Resolution or Adjust Resolution option from the left column.
4. Expand the drop-down menu next to “Multiple displays” and select Duplicate these Displays.
5. Click OK to apply the changes and close the window.

Windows 7 / Vista

1. Click the Start button and select Control Panel.
2. Click Appearance and Personalization, then click Display.
3. Click the Resolution or Adjust Resolution option from the left column.
4. Expand the drop-down menu next to “Multiple displays” and select Duplicate these Displays.
5. Click OK to apply the changes and close the window.

Windows XP

1. Click the Start button and select Control Panel.
2. Double-click Display.
3. Click the Settings tab.
4. Un-check the box beside Extend my Windows desktop onto this monitor.
5. Click OK to apply the changes and close the window.

Video splitters take the output for monitor port 1 and mirror it to the remaining outputs. By default, the first output port is the master port that is mirrored to each additional monitor. Make sure that you use the first output port when you use the video splitter. The master port is labeled on the splitter boxes from StarTech.com. On the splitter cables from StarTech.com, the master port is the top port.

If you are having issues with a splitter interpreting the incorrect port as the master port, try the following:

1. Unplug all of the video connections.

2. If the splitter is powered, power cycle the splitter.

3. Plug in all of the video connections again.

4. Make sure that the first video connection plugged in is the one that you want to be the master port.

When you troubleshoot issues with an MST hub, there are some quick tests that you can complete to rule out potential problems. You can test to make sure that the following components are working correctly and are not the source of the issue:

• Video cables

• Video source

• Video destination

• MST Hub

To test your setup components, try the following:

• Use the video cables, video source, video destination, and MST hub in another setup to see if the problem is with the components or the setup.

• Use a different video cable, video source, video destination, and MST hub in your setup to see if the problem persists. Ideally, you should test a component that you know works in another setup.

When you test your cables, it is recommended that you do the following:

• Test each cable individually.

• Use short cables when you are testing.

• Eliminate the use of adapters, extenders, or splitters where possible.

When you test the MST hub with your computer system, do the following:

• Make sure that the computer/graphics adapter is MST compatible. For more information, refer to the following FAQ: http://www.startech.com/faq/mst-hubs-gpu-compatibility.

• Make sure that the latest graphics drivers are installed. The latest drivers are available on the website of the manufacturer of the graphics adapter.

• Use compatible adapters. For example, DisplayPort to HDMI and not HDMI to DisplayPort.

Note: Drivers are not required for the MST hub.

To check to see if Windows is detecting the monitor, on a computer that is running a version of Windows 8 or Windows 10, do the following:

1. On your keyboard, press the Windows key + X and click Control Panel.
2. Click Appearance and Personalization, then click Display.
3. In the left column, click Resolution or Adjust Resolution. Your monitors will be displayed as numbered icons.
4. To see which monitors are detected, click the Display menu.
5. To display the numbers on each of the connected monitors and see how the operating system has assigned their positions, click Identify.

To check to see if Windows is detecting the monitor, on a computer that is running a version of Windows 7, do the following:

1. Right-click on the desktop and click Screen Resolution.
2. To see which monitors are detected, click the Display menu.
3. In the left column, click Resolution or Adjust Resolution. Your monitors will be displayed as numbered icons.
4. To display the numbers on each of the connected monitors and see how the operating system has assigned their positions, click Identify.

If you are experiencing flickering issues with the MST hub, your monitors may be at a 59 Hz refresh rate. If they are at 59 Hz, you need to adjust the refresh rate to 60 Hz. In order to change your monitor's refresh rate, complete the following:

1. Right-click anywhere on your desktop.
2. Click Screen resolution or Display settings.
3. At the top of the screen, select the monitor that you want to change the refresh rate for.
4. Click Advanced settings or Display adapter properties.
5. On the Monitor tab, click the Screen refresh rate drop-down list.

Note: This step may vary depending on your operating system and graphics card.

If the displays connected to your MST hub do not wake up after your computer goes to sleep, change the input on the monitor(s) from Auto to the correct input (for example, DisplayPort or HDMI). This prompts the monitor to send its identification data to the correct port instead of scanning for ports when the signal is lost.

After you select the correct input on the monitor(s), press the Scan button to initiate the handshake (EDID) process. For more information on the Scan button, refer to the following FAQ: http://www.startech.com/faq/mst-hubs-scan-button.

If you set the monitor to the correct video port and press the Scan button and the issue is still not resolved, you need to disable sleep mode on your computer. To disable sleep on a computer running a version of Windows, complete the following:

1. Open Control Panel.

2. Click Power Options.

Note: Depending on how you have the View by options set in Control Panel, you might have to click Hardware and Sound to see Power Options.

3. Click Change plan settings for the plan in use.

4. For both entries, change Put the computer to sleep to Never.

5. Click Save Changes.

By default, most systems will duplicate to multiple displays when a MST hub is attached. If you are getting mirrored displays and cannot detect more than one display in Screen Resolution or Display Settings, your graphics card may not be compatible with MST. For more information about how to determine if your graphics card is MST compatible, refer to the following FAQ: https://www.startech.com/faq/mst-hubs-gpu-compatibility. 

If you are using a version of Mac OSX, refer to the following FAQ for more information: https://www.startech.com/faq/mst-hubs-mac-osx-support.

In order for your mouse to move properly between your monitors you must rearrange your monitors in Windows to match the physical location of your monitors on your desk. To do so, complete the following based on your operating system:

Windows 10 and Windows  8

1. On your keyboard, press the Windows key + X and select Control Panel.
2. Click Appearance and Personalization, then click Display.
3. Click the Resolution or Adjust Resolution option from the left column, which will display your monitors as numbered icons.
4. Click Identify to display the numbers on each connected monitor, showing how the operating system has assigned their positions.
5. Click and drag the monitor icons to best match your physical setup.
6. Click OK to apply the changes and close the window.

Windows 7 and Windows Vista

1. Click the Start button and select Control Panel.
2. Click Appearance and Personalization, then click Display.
3. Click the Resolution or Adjust Resolution option from the left column, which will display your monitors as numbered icons.
4. Click Identify to display the numbers on each connected monitor, showing how the operating system has assigned their positions.
5. Click and drag the monitor icons to best match your physical setup.
6. Click OK to apply the changes and close the window.

Windows XP

1. Click the Start button and select Control Panel.
2. Double-click Display.
3. Click the Settings tab, which will display your monitors as numbered icons.
4. Click Identify to display the numbers on each connected monitor, showing how the operating system has assigned their positions.
5. Click and drag the monitor icons to best match your physical setup.
6. Click OK to apply the changes and close the window.

To mirror the image from your primary monitor instead of extending your desktop, refer to the following FAQ: http://www.startech.com/faq/Windows_Mirroring_Monitors

If a DisplayPort converter with audio is not passing sound from the source to the destination, complete the following:

1. Make sure that the DisplayPort connection on the video card is the default audio playback device.
2. Make sure that the video card has the DisplayPort audio codec installed. If not, visit the video card manufacturer's website to find out how to update the video card driver.

To output 4K to a DisplayPort display at 30Hz, your monitor must support the resolution and refresh rate. If your monitor also supports 4K at 60Hz (DP 1.2 or higher), you may also need to set the monitor to work at 30Hz. 

To resolve this issue, use the buttons on your monitor to change the DisplayPort settings to DP1.1. For more information about how to change your monitor settings, refer to the website of the manufacturer of your monitor.