Why do eyes hurt from a monitor with an IPS matrix?

Question

Monitors

Good afternoon dear experts. I recently purchased an HP-22FW monitor with an IPS matrix, FHD resolution. And, practically, immediately noted that my eyes began to get very tired when working on it. The frequency of the monitor is 75 GHz. I read about flickering modern monitors, but this one has Flicker-Free. Played with brightness, contrast. So far, it doesn't make any sense. The eyes are still very tired and sore. There is no such thing behind another square Samsung monitor (1280x1024) of furry years of release. I can stare at it all day and everything is fine. What could be the reason? What do you advise? Maybe it's worth digging deeper into the settings?

Answer 1

The most banal reason is that the monitor has a different size, the eyes need to run more to cover the entire surface. In theory, it will pass when the eyes get used to it.
Or, for example, a different angle at the monitor, not familiar.
Or let's just say it coincided, the eyes began to get tired due to deterioration of vision.

Answer 2

Set the flicker to 60 Hz.