StarTech.com MSTCDP123HD Troubleshooting

• Make sure the USB-C port supports video also called DisplayPort alt-mode. Not all USB-C
ports support video.
• Make sure a supported operating system is being used. macOS is not supported.
• Verify the maximum number of displays supported by your GPU; Some GPU chips (such as
Intel HD Graphics) are only capable of supporting a maximum of three displays (laptop
screen may be disabled when connected to three monitors). Make sure not to exceed that
number.
• Check that the video card (or onboard graphics) drivers are up to date.
•
Double-check you are not exceeding the total amount of video bandwidth the MST hub can
support. You can test by using lower resolutions monitors. Note: supported display
configurations can be found on the product page on the StarTech.com website.
•
If the video signal goes in and out, try using shorter HDMI cables or higher quality cables
like HDMM1MP or HDMM2MP.
•
We do not recommend using an MST hub connected to a laptop docking station or KVM
switches.
•
If the displays are not waking from sleep, unplug the hub from the computer and remove
the power cord (if applicable). Disconnect the video cables connected to the hub. Wait 10
seconds. Reconnect the hub to power and connect it to the PC. One by one connect the
video cables; waiting a few seconds between each. Check Display Settings to ensure the
display configuration is correct (resolutions, locations, extend/clone).
•
Avoid using a 4K 60Hz display even when used at a lower video resolution. Some 4K
displays reserve the full bandwidth they need even when set to lower resolutions. It may
prevent other displays connected to the MST hub from working.
Troubleshooting: USB-C to HDMI MST Hubs