Also on your Win10 machine look at display scaling. This may help. Once you get around or past a resolution of about 2560×1600 then the standard 1:1 scale can get way to small on a 4K monitor.
Settings>System>Display and adjust the slider. Might help.
Another thing to try which can be an issue is running multiple monitors with differing display resolutions.
Does S3D display the same behaviour on the 4k if it is the only monitor?
it is not a hw problem, if the problem was that hdmi is not fast enough for that amount of pixels (it is not, that's why you have to run 30hz, upgrading to displayport will probbly give you 50-60hz on the same screen) there would not be an image on the screen, but since there is an image on the screen it has nothing to do with drivers &| cables &| connectors but with software bug
I have the exact same problem with my K2100M NVIDA graphics card in 4K mode. I have an HP zbook G2 15. Some of the symptoms are windows within windows, windows smear when moving, parts drop in at funny angles and the center of view rotation/zooming moves outside the view window. This is often remedied by resizing my window in any way. It sounds like this happens on two or more different graphics cards.
Yes, I should have said that my old 3.1 version did run fine on my 4K monitor with exactly the same graphics settings that now produce the problem I showed in the first post.
So is it generally agreed that this is a software bug in 4.0? It seems pretty clear to me that it is.
Right-click the Simplify3D.exe program file and select Properties/Compatibility. Then check the box "Override high DPI scaling behavior" and accept the System option for Scaling performed by. Then click OK to make the change.
Very interesting - my version is Win10/64 Home Ver. 1703 Build 15063.608. This is the Fall Creators Update (whatever that means.) You should be able to get it by using Windows Update. It installed fine for me.
PS: I don't know if it matters, but I have an nVidia graphics card driving my 2 monitors.