Dual external monitors stopped working

[JPB95]

My laptop has video output capability through the USB-C port:

       1 USB Type-C® 10Gbps signaling rate (USB Power Delivery, DisplayPort™ 1.4, HP Sleep and Charge)

Three months ago, I purchased a USB-C adapter from Amazon that could allow me to connect one external monitor through DisplayPort, and another through a HDMI cable. After setting them up, I was able to have both external monitors and my internal display working fine (so, triple extended monitor setup).

A month ago, I unplugged my adapter to go to a meeting. When I returned two hours later, I plugged the adapter, but the external monitors did not wake up. If I unplug any monitor, the other one wakes up and works fine. But none of them work if they're plugged in at the same time. At first I thought about a faulty adapter, so I contacted the seller on Amazon, and I got a replacement. This problem is still persistent with the new adapter.

I've tried updating graphics drivers, rolling back to previous drivers, restarting the computer, and nothing has worked. I found a temporary solution which is to use the adapter with the DP monitor only, and plugging in the HDMI monitor directly to the computer's HDMI port. This works fine, and I can use both monitors, but I would prefer connecting both monitors through the adapter.

[Irwin6]

Hi @JPB95,

Welcome to HP Support Community.

Thank you for posting your query, I will be glad to assist you.

I see that you are facing an issue using multiple monitor's on your Laptop.

Follow the below steps to fix the issue.

-Perform a power drain on your PC.

1) Unplug the power cord from the PC & wall.

2) Disconnect the power cable from the AC adapter if it is a detachable part and keep it aside.

3) Press and hold the power button down for 15 seconds and release the power button, wait for about 30 seconds.

4) Plug the power cord back into the AC adapter, then connect it to the wall and to the charging port on your PC.

5) Power on the PC

-Kindly refer to the steps on this link to update the BIOS and let me know if that resolves the issue.

Make sure you keep only the charger plugged in while updating the BIOS for your PC.

Click on the + sign next to BIOS and then download the file.

Open the file and follow the on-screen instructions to complete the update.

-Please install all the pending updates for the Windows operating system following the below steps.

go to Start > Settings > Update & Security > Windows Update and select Check for updates. If the upgrade is available for your device and you want to proceed, download and install it.

Please click “Accepted Solution” if you feel my post solved your issue, it will help others find the solution. Click the “Kudos/Thumbs Up" on the bottom right to say “Thanks” for helping!

I hope this helps.

Take care and have a great day ahead!

 Irwin6

HP Support

[JPB95]

Hi @Irwin6,

Thanks for your suggestions. However, this did not seem to work. I performed the power drain, and the monitors are still not recognized through the USB-C dock. I also made sure that my BIOS was up-to-date.

I did notice that in the BIOS, there is an option to 'enable high-resolution mode through USB-C DP dock' or something like that. I had it disabled, so I turned it on, and I plugged in the dock. When the computer finished restarting, the HDMI monitor (plugged through the dock) turned on, but the DP monitor stayed off. I tried unplugging/re-plugging the DP monitor, and then both monitors turned off. My guess is that there is something preventing enough power being delivered through the USB-C to power both monitors at the same time. Do you know if there is a way to test how much power is being delivered?

[Irwin6]

Hi @JPB95,

I am sorry to hear that the above steps did not help much but i do appreciate your efforts in performing the troubleshooting steps.

The support here is limited to troubleshooting as you have exhausted all the possible steps to fix it and this issue might require one-on-one interaction to assist you further.

I've sent you a private message with the instructions. In order to access your private messages, Click the Private message icon on the upper right corner of your HP Community profile Next to your profile Name, you should see a little blue envelope, please click on it or simply click on this link

Take care and have a great day ahead!

Irwin6

HP Support