Windows 10: Dual monitor troubleshooting

I'm trying to troubleshoot a dual-monitor setup and could use some help.

I've spent hours on the phone with Samsung support, and I still don't really know whether it is a hardware or software problem. I sent the monitor to Samsung to repair, and they replaced the PCB, but it's still not working correctly. But their "troubleshooting" capability was limited to telling me to: (1) reset the monitor, (2) unplug and replug it, and (3) try a different cable. None of which inspires confidence.

The monitor works correctly about one time in three. When I get it working, everything is fine. When I don't, it can exhibit any combination of the following symptoms:

• Black screen, no image, monitor's built-in menu may or may not show
• Power light on monitor may be on or off
• Windows may or may not detect the monitor, as reflected in display settings
• Screen may be stretched to the wrong resolution
• Screen may appear at the right resolution, but wallpaper too small for the screen

Generally, when it is not working, it requires a complete restart, unplugging and replugging power and monitor, etc. to get it working correctly. Sometimes I have to do this multiple times.

System details:

• Computer: Lenovo X390
• OS: Windows 10 Pro 1909 18363.693 (recently updated)
• Graphics card: Intel UHD Graphics 620
• Graphics driver: Intel 26.20.100.7528 dated 11/13/2019
• External monitor: Samsung LS24H850QFNXZA 2560x1440
• Monitor driver: Samsung 1.0.0.0 dated 1/5/2017 (the most recent version available on Samsung'g web site, as of today)
• Monitor cable: USB-C

I've already done all the "uninstall and reinstall the driver" sort of things. Can anyone suggest where to go next? I spent the last ten years using only Linux, so my Windows is a bit rusty. Don't even know where to look for error logs, etc.

Any help much appreciated.

:)

 

Dual Monitor Setup & Speakers

Hi,

There are several factors which could prevent your dual monitors and your speakers from working properly. In order for us to effectively assist you with your concern, we just have a few questions for you:

• Are you getting an error message/code when trying to run the dual monitors?
• Have you tried running the hardware troubleshooter?
• Have you tried running the System File Checker tool?
• What troubleshooting steps have you already performed?

Regards.

 

Windows 10 Update - Now my dual monitors do not work

Hi,





One of the possible reasons why Windows 10 was unable to detect your dual monitor is an outdated or incompatible graphics driver. To best address your concern, we need you to answer the following questions:

• Which Windows 10 build are you using?
• Have you already tried performing the troubleshooting steps suggested by
  Mauro Cavallin on June 16, 2017?
• Are both of the monitors not working just like what the original poster was experiencing? If yes, have you tried disconnecting one of the monitors? What was the outcome?
• What troubleshooting steps have you done so far?

We will be waiting for your response.

 

Windows 10 Dual Monitor issue

Hi Lisa,

For us to better assist you with your dual monitor issue in Windows 10, we'd like to know the following:

• Were there any changes made to your computer prior to this issue (Windows updates)?
  
• What troubleshooting steps have you tried to resolve this?
  

We're looking forward to your reply.