I did the math on this site and I'd have to hunch less than a foot from the screen to hit 35 PPD on my work provided Thinkpad X1 Carbon with a 14" 1920x1200 screen. My usual distance is nearly double that so my ppd normally is more like 70 ppd, roughly.

https://phrogz.net/tmp/ScreenDensityCalculator.html#find:dis...