Plugable UD-3900c4 suddenly stopped working with Lenovo Ideapad Flex 5

[JCORTEZC]

I have the above LapTop and a ThinkPad. the Plugable still works fine with the ThinkPad but not with the Idea Pad. What feature of the IdeaPad failed, and what feature should I make sure Ihave on a new PC for all 4 of the HDMI ports ( ports 3 &4) [Alt mode MST?]

[adi]

Hi there,

Welcome to the community!

I am sorry that your UD-3900C4 is not working as expected with your IdeaPad Flex 5.

From what I can find, the Flex 5 does not support DisplayPort Alt Mode MST, which is required for the HDMI 3 and 4 ports on the UD-3900C4 to output video.

Based on the specifications, this port only supports PD.
1 x USB 3.1 Gen 1 (Type-C™) with PD

To fully utilize the UD-3900C4, your system will need to support both Power Delivery and DisplayPort Alt Mode MST. Unfortunately, this isn’t always obvious in manufacturer specifications, so if you are unsure, it’s always best to contact them directly and ask.

Please keep in mind that Apple does not support DisplayPort Alt Mode MST. If you are considering getting an Apple laptop in the future, this will be important to remember.

I hope this helps!

Adi
Plugable Technologies

[JCORTEZC]

Thank you for your fast response. I am aware that my PC does not have the feature that would enable it to use ports 3&4. When I first got the Plugable, my PS was able to use poets 1 & 2 so I was still able to run 2 monitors. About 3 weeks ago, I lost ports 1 & 2. I suspect my PC as my work PC is still able to use 3 monitors. Does this mean my PD is malfunctioning? If I am looking for a new PC what features should I be looking for besides PD and DisplayPort Alt Mode MST? Are there different flavors of PD?

[adi]

Hi there,

Thank you for the added context. I wasn’t aware you were having issues with the HDMI ports that utilize DisplayLink technology. This is likely related to the DisplayLink drivers. I am happy to help you troubleshoot to see if we can get those two displays back up and running. Please follow the instructions I’ve included below if you are interested.

Can you please email our direct support email address ( support@plugable.com) with “For ticket # 439282” in the subject line? In the email, please include the following information:

• Please provide the Amazon Order ID number for your Plugable product purchase.
  For your reference, an Amazon Order ID number has seventeen digits (separated by two dashes), and typically that information can be found here → https://amazon.com/orders
• Can you please keep the UD-3900C4 connected to your computer (even if it is not working as expected) and send us the output of our diagnostic utility PlugDebug? → https://plugable.com/pages/plugdebug 1

This will allow me to examine log files from your computer and help determine the next steps.

Please do not post the above information here in our public forum (it contains personally identifiable information)

When looking for a new PC or laptop, it’s essential to focus on two main features: Power Delivery and DisplayPort Alt Mode MST. These features are necessary for any docking station that provides power to the laptop and uses DisplayPort Alt Mode MST (Multi-stream Transport). USB Power Delivery comes in different versions, each improving on the last by enhancing efficiency and power capacity. When considering Power Delivery (PD), it’s crucial to understand your laptop’s power requirements and whether the USB-C port supports charging the host system. Once you have this information, ensure your PD-compliant docking station or power adapter can supply the necessary wattage to charge your laptop.

If you have any questions, please don’t hesitate to let me know.

Thank you,

Adi
Plugable Technologies