Problems whit Samsung C24F390FHU (Flicker, Horizontal lines) !

Hello

I have some strange problems whit my monitor Samsung C24F390FHU (SVA panel).

When i am using it, i see some kind of flickering in the right corner of the screen. This is visible where the windows 10 default wallpaper is, (the 4 windows). When i am reading text on the screen i see for a few seconds some kind of horizontal lines in front of my eyes.

This happens when a web page has a dark background and white txt.

At firs i though that my old desktop Pc had problems, because of that i bought a new one. Sadly the same problems remained.

New Pc Spec
Cpu: Amd Ryzen 5 2600
Motherboard: Asus ROG Strix B450-F Gaming
Ram: Kingston DDR4 8GB PC2400 HX FURY RED

The Gpu is Gt 710 1gb, i bough it for testing, the monitor is connected to the gpu using HDM cable (1080p).

I connected the monitor to a friends computer, the Gpu is RX 550 4gb, the monitor had a bit less flickering, but my eyes started to get dry. After some time i started to get headaches behind my head, some kind of pressure . When i red txt on the monitor connected to the Gpu RX 550 i did not see the horizontal lines.

What Gpu is less "stressful" for the eyes AMD RX 570 or GTX 1060?

On some forums i had red that AMD uses temporal dithering. Can this cause headaches?

Before this problem started i was using the Gpu AMD 4890 1gb. The Gpu was connected (VGA) to the monitor Iiyama AS4611UT (MVA panel) .

The brightness of the monitor C24F390FHU is 41%.

Can somebody give me nay advice.

I might even buy a new monitor. Is the iiyama ProLite X2483HSU-B3 a good choice?

The second option is BenQ EW277HDR. Although some reviews critisize the text quality.

"I wouldn’t recommend going for 1080p on a 27in monitor, as the pixel density on a screen of this size starts to look a bit small when you’ve only got 1920×1080 pixels to play with, resulting in jagged edges in text and desktop icons. It’s fine for the most part, but everything is just fuzzy enough to make you second guess whether you need another trip to the opticians. Personally, I would normally recommend a 2560×1440 resolution on a 27in monitor, but then you’re looking at paying a lot more for the privilege."

https://www.rockpapershotgun.com/2018/05/30/benq-ew277hdr-review-a-fantastic-budget-hdr-monitor/

"The large screen size combined with the FHD resolution also means that sometimes text can be a little blurry to read without zooming in, which is a problem if you’re reading long pdf files or web pages. The B.I+ did a fairly good job of ensuring that the display was comfortable to look at throughout the day, so kudos to BenQ for this rather smart feature."

https://www.techradar.com/reviews/benq-ew277hdr-monitor