First you can check your device manager if you have any display adapter drivers that have stopped working. If you have an Intel driver that has stopped due to a problem there may be a work around.
We found that if you opened the laptop lid and then restarted the computer, the external monitors would identify and work. You could then close the laptop screen and continue working but whenever the laptop is turned off or undocked it would need to have the screen open in order to identify the monitors.
This is by no means a long term solution but it seems like this is a problem with Win 10 and will hopefully be fixed in the near future. I haven't tested it yet but I also so that Nvidia pulled their driver from last week due to some display issues so maybe that was the problem.
Answer from TheSeldonPlan on Stack ExchangeFirst you can check your device manager if you have any display adapter drivers that have stopped working. If you have an Intel driver that has stopped due to a problem there may be a work around.
We found that if you opened the laptop lid and then restarted the computer, the external monitors would identify and work. You could then close the laptop screen and continue working but whenever the laptop is turned off or undocked it would need to have the screen open in order to identify the monitors.
This is by no means a long term solution but it seems like this is a problem with Win 10 and will hopefully be fixed in the near future. I haven't tested it yet but I also so that Nvidia pulled their driver from last week due to some display issues so maybe that was the problem.
This may be useful to some. My computer is a Lenovo W530 and with the same issue, after I reinstalled Windows 10, the monitors connected to the DVI ports on the dock, did not work. This computer has a second video card Nvidia Quadro and I went to Windows system directory and found an application which is the control panel for the Nvidia. There all I had to do was to enable the monitors on DVI ports and it all worked. Perhaps on Dell the solution is similar. For some reason, Windows 10 installation does not add a shortcut for the Nvidia control panel as it does for the Intel Graphics that only controls the laptop screen, so I had to hunt for it.
USB-C is not working with external monitors - MiniBook - CHUWI | Official Forum
USB-C to HDMI suddenly stopped working
USB-C to HDMI adaptor not working on Windows 10 on Dell G15 Notebook | Windows Central Forum
Monitor-not-working-through-Usb-c
Videos
Not all USB-C ports support video output. You should check the specifications on your particular model.
Only USB-C port with USB 3.1 or above version can stream video.
Hi Lucy. I'm Greg here to help.
I see a lot of reported issues with USB-C to HDMI adapters, in fact any adapters for monitors in Windows are very likely not to work for many reasons because the native method is always much, much better.
But you can troubleshoot USB-C to HDMI monitor connections not working to see if one of these fixes work - I've collected them all:
https://sortatechy.com/usb-c-cable-with-monitor/
https://www.partitionwizard.com/partitionmanage...
https://usbcafe.com/usb-c-to-hdmi-not-working-s...
https://uniaccessories.com/blogs/blog/solved-us...
https://www.youtube.com/watch?v=7IRLYIXz2TA
Feel free to ask back any questions. If you'll post back detailed results then I may know what to suggest next, if necessary.
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I have been using an HDMI cable + HDMI to USB-C adapter to connect two monitors to my laptop. My main monitor is directly plugged in to the HDMI-socket, and the USB-C adapter to the only USB-C socket on the laptop. It's been working flawlessly until yesterday. Now the second monitor just displays "No HDMI signal" and goes to sleep mode. It does not even recognize me plugging in the USB-C cable. Take note that I've done zero (0, nil, no) changes to my setup.
Naturally I thought that the adapter was faulty since I did some testing with the USB-C socket (it charged my iPhone), and the HDMI-cable was working. Purchased a new HDMI to USB-C cable but to no avail.
On my laptop the device manager shows my monitor as a "BillBoard Service".
Has anyone run into this problem? Google is not my friend in this matter, even though I am a man of lurking the internet. Can someone point me in the right direction here?
Many thanks.
Edit: Okay so it got solved by turing the laptop off, then holding the on button for 30 seconds and letting go. What this triggered I have no idea but it might help someone out.