- Edited
Right now my best setup is GTX 970 -> Windows 7 (it matters to my symptoms) -> BenQ EW2750ZL. I haven't tested VGA vs HDMI so I just use VGA to be on the safe side. 90% of my screen time is spent on this setup.
For movies and TV I use an HTPC with GTX 650 -> Windows 7 -> Panasonic ST60 plasma TV and that is also comfortable. This is probably the most comfortable setup but it's not that practical.
iPhone 7 Plus is the best smartphone I've used in a long time. It still could be better but I can use it long enough to get what I need to done and then get out quickly (a couple of minutes) without causing a headache.
iPad Air 1 used to be a really good device but now it is just average since I upgraded it to iOS 10. Average just like the iPhone 7 Plus, but maybe a bit worse.
None is as comfortable as I would like though and are cumulative in their effects necessitating a complete break from screens for a few days every couple of weeks.