*sets up HDMI audio passthrough*
*plugs in stereo speakers to the monitor's audio out*
*Taylor Swift*
For a moment, when I pulled a black-to-white gradient on Paint.NET, I saw lots of steps.
Zooming in reveals that the display is showing the difference between, well, pretty much every step, and that the display is displaying it as-is without dithering. All the ugly truths uncovered by a better monitor.

This got verified when I went to monitor test sites. (Paint.NET is not capable of dithering gradients, unlike GIMP or Photoshop)