The first thing you should do is check the optimum resolution for your display. This will usually be mentioned in the product listing on the display manufacturer’s website. If it’s not there, it will be mentioned on the box that the display shipped with. In some cases, after you connect it, the display will show a dialog box onscreen with the correct resolution.

Once you’ve determined the right display resolution, open the “Settings” app on your Apple TV.

Next, select “Video and Audio.”

Navigate to the “Format” option.

This page shows some standard display resolutions such as 4K HDR 50Hz, 1080p SDR 60Hz, etc. Here, you can select the resolution for your display.

The only issue is that these are not exact values and may not match the recommended resolution for your display. To get that, scroll to the bottom and select “Other Formats.”

This is where you’ll see exact display resolution values such as 2560×1080 HDR 60Hz, along with other resolutions not mentioned on the previous screen. Select the correct display resolution here.

If Apple TV manages to switch to the correct resolution, it’ll show a message that states that it was successfully able to change the resolution. Choose “OK.”

That’s all you need to do here. In case the switch to a different resolution is unsuccessful, you might see a black screen for several seconds, and your display could even switch off on its own. Press the Menu button on your Apple TV remote to return to the original resolution, and then you can try to change it to a compatible resolution again.