@Wyldanimal On a Large format Full HD ( 1080p) Screen 40" or larger, you might see better clarity by Down scaling 3K size to 1080p size, but that is at the cost of CPU cycles.
Probably the same way a console like the Xbox One X with a 1080p screen use 4k texture, and downscale it to 1080p, with sharper details and clarity.
I use my hdtv with iStripper, so i should try to compare 2 shows, one at 1080p and the other at 3k (release on may 23 or after) to see if i see a difference in detail.
And if yes, time to add a bigger external hardrive.
@Dordai6 I'll expand on what @Wyldanimal said. You might notice some better quality at the cost of CPU cycles if you play 3K cards as a scale greater than 80% on a 1080p screen. This is because a 1080p card is designed to be played at about 75% on a 1080p and beyond that it must be scaled up and will be a little less detailed than a 3K card played at the same scale.
Also very useful info, thank's
i play all show bigger than 80% (even in small mode), so i should see a difference.