I first started having these eye strain issues about 9 years ago when I got a new nvidia 750ti gpu. Had never experienced anything like it before. I was used to being able to stare at my computer screen for hours a day without problems on my previous geforce 8800GT. Suddenly I could hardly stand it for 15 minutes. And the worst part of it, the eyestrain would make my eyes sensitive to everything else. After using my computer, I could barely look at my tv my eyes were so fatigued. Just going shopping would give me headaches from all the visual scanning required. I tried various brightness settings, etc. I tried different monitors new and old (relative to 2014), but the eye problems persisted. Went to eye doctor, nothing wrong with my eyes.
I ended up getting a used pc with an amd a8 apu. No eyestrain, things were back to normal for that time. 3 years later, I get a new pc with an i7 and gtx 1060. Eye problems returned. Got some expensive gaming glasses to reduce headache and eyestrain, and those helped somewhat. My next machine was a ryzen3 laptop w/ vega 3 mobile graphics. Whenever I used the laptop, I experienced no eyestrain. Whenever I used my desktop pc (gtx1060), I experienced eyestrain. Fast forward to the present, I recently picked up a new desktop pc with a ryzen 5 and nvidia 3060ti. Eyestrain!
Can't really draw any conclusion yet since my nvidia cards that caused issues were comparatively much more powerful than the amd graphics which didn't. I guess my next step will be to switch my gpu for an rx 6000 series one and see.