How to connect Dell monitor correct

Hi PeterElkjær,

Thank you for reaching out Microsoft Community. We apologize for the inconvenience this has caused you.

I assumed you are using a Mini-DP to HDMI adapter to extend your Surface display to your Dell monitor with the dock. In this case, I'd like you to clear the display cache. See Solution # 5 from this link https://support.microsoft.com/en-us/help/4023496/surface-troubleshoot-connecting-to-a-second-screen to clear the display cache.

Once done, uninstall the monitors that were recognized by your Surface device.

Open Device Manager

Expand Monitors. If what shows in the drop down is just the Surface Panel Filter, click View tab from the options available at the top and click "Show Hidden Devices". If it shows those monitors previously connected to the Surface device, kindly right-click those monitors and remove the monitors by choosing uninstall device. After uninstalling, restart your Surface, disconnect it from the dock, unplug/re-plug the dock from the power outlet and disconnect/reconnect the HDMI cord. After reconnecting everything, kindly check if extending your Surface display now works. 

You  may also have to set  the 2nd display in Display Settings to it's right resolution (Dell display's resolution  ( 2560 X 1440 @ 60 Hz ). The Surface Laptop 3's resolution should be set to recommended and you have to press and hold Windows key + P and choose extend instead of duplicate and see if the resolution on your Dell monitor is much better.

If this helps, feel free to let our Community know by marking this post as an answer. Otherwise, don't hesitate to respond to this thread for further assistance. I am always here to help. 

Kind Regards,

Crest_Z 

Hi Crest_Z 

Thanks for your reply.

Yes, I can get an image using Mini-DP to HDMI adapter. I also have a DP to Mini-DP cable, but no image at all using this.

Okay so I cleared the cache. No change.

I have tried to extend monitors insted. I can't (whatever I do) choose 2560x1440  - if I only choose to use screen 2 (the Dell), I can't choose resolution at all.

also - the Dell Display Manager Software does not detect that a Dell screen is connected - so I cant open the app.

So right now, I have an image on the Dell Screen, buts its not very clear (I get headache of watching it hahaha).

Hi PeterElkjær,

Sorry for the delayed response.

Have you tried connecting your Surface device directly to the external monitor? For the mean time, you can utilize the USB-C port of the Surface Laptop 3 and use an adapter (USB-C to HDMI adapter) to extend your Surface display to the monitor (if there's available HDMI-IN port at the back of your Dell Monitor). This helps us determine whether the issue happens because of the dock.

If this helps, please let me know and don't hesitate to respond to this thread if you need further assistance.

Kind Regards,

Crest_Z