No Signal after changing refresh rate

Sorry to hear it. Please try power cycling the console by holding the power button on it for 10 seconds till it shuts down. Then unplug it for 30 seconds. When you power on quickly hold the Sync button (left side near the USB port on the original Xbox
One and just below the power button on the S and X consoles) and the Eject button for the console until you hear a second start up noise.

You should now see a new screen. Scroll over to Restart/Reset and reset the console to factory settings. There is an option to keep installed games and apps so you won't need to redownload them.

Hi Thomas,

Thanks for letting us know it is working now. I will go ahead and lock the thread as it has been resolved. Feel free anytime to come back if have an issue, a question, or just want to chat with fellow gamers.

Thanks,

Brad

We tried this and it's working fine now. Thanks!

Hi there!

Thank you for coming to the forums. I'd be happy to help.

I recommend
resetting the console's display settings. Here's how:

1. If there's a disc in the Xbox One console, eject it.
2. On the console, press and hold the Xbox button for five seconds to turn off the console.
   
3. Press and hold the Xbox button and the Eject button until you hear a beep to turn on the console. You will hear one beep right away and a second beep 10 seconds later. The power light will flash on before the second beep.
   DO NOT LET GO until the second beep occurs.
   Note This will boot your console in low resolution mode (640 × 480). To reset this setting, go to
   System > Settings in the guide, select
   Display & sounds, Video options, and then TV Resolution.
   
4. If you are required to complete these steps on every boot-up, you will want to change your TV connection to HDMI as shown in step 3 in the next section, "Your screen is blank and you use an AVR in your setup." For more information, see How
   to adjust the display settings on your Xbox One console.

If you cannot reset the display settings, then follow the soft factory reset option suggested by Onyx.

Let us know if this helps!

You set resolution, not refresh rate. Anything with HDMI should be able to accept 1080p signals

Since it's a monitor, the most likely reason for incompatibility is refresh rate as you surmised. Many computer monitors have nonstandard alterations to the refresh rate, and cheaper models often only have one mode, which sacrifices compatibility with general consumer devices. Please let us know the model of the monitor in question.,