Windows stopped detecting monitor over DisplayPort

[noktulo]

I've had my Envy 27" 4K monitor connected via DisplayPort for a while. Recently, Windows has stopped detecting the monitor.

The monitor is hooked up to my GeForce GTX 1070. I know both DisplayPort ports work on the graphics card because my other monitor is connected via a DisplayPort->HDMI cable, and it works on both the graphics card's DisplayPort ports. I also have replaced the DisplayPort cable, and that didn't fix it. The monitor does work when connected via HDMI, so it's the DisplayPort specifically that's causing the issue.

I'm on the latest NVidia driver and update of Windows 10. 

[A4Apollo]

Hey there! @noktulo, Thanks for stopping by the HP Support Forums!

I understand you have issues getting the external monitor detected on your PC.

Don't worry I'll try to help you out.

Did you make any software or hardware changes on your PC?

Are you using a straight display port cable or an adapter to connect the monitor?

Try the monitor on another computer to ensure that the monitor is functional?

Please provide the product number of your PC to assist you better.

As you mentioned you you have connected the monitor using a display port cable but still, the monitor is not getting detected on your PC.

Try checking with a different monitor or different cable and check if it helps.

Press Fn key + F4 key to extend the displays.

Extend your display by changing display settings.
a. Open Screen Resolution by clicking the Start button, clicking Control Panel, and then, under Appearance and Personalization, clicking Adjust screen resolution. 
b. Click the drop-down list next to Multiple displays, click Extend these displays, and then click OK.

Also, If the monitor has a factory reset or restore option, set it. Press the Menu button on the front panel and select Factory Reset.

If the issue still persists uninstall the graphics driver from device manager and install the latest graphics driver and BIOS on your PC.

If you are using an HP PC, You can update other drivers on your PC using HP support assistant.

Refer this article to know more information about using HP support assistant.

Refer this article to know more information about Connecting a Monitor, Projector, or TV.

Also, refer this article to further troubleshoot No Signal, Signal out of Range issues.

If the solution provided worked for you, please mark accepted solution for this post.

Let me know if this works!

I hope you have a great day! 🙂

Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution.

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