What is the NVR, DVR, or recorder’s default monitor resolution?
The NVR / DVR display resolution by default will be set to 720p to ensure compatibility with most displays. You can change this by going to: Menu-Configuration-VGA/HDMI Resolution
Now you will be able to set the resolution to match your display/TV.
Why set it to 720p?
Compatibility.
If you have a 4K TV and we set it to 720P, you will see something.
If you have a 720P TV and we set it to 1080P, nothing will display at all.