Thank you for that tip. I had a lot of screen tearing before I enabled that option.
Do you have "Force Full Comoposition Pipeline" enabled or just "Force Composition Pipeline"?
EDIT:
https://wiki.archlinux.org/index.php/NVIDIA/Troubleshooting#...
That's helpful! :)
I'm on Linux, and as long as I have screen composition on in the NVidia Settings Panel and software vsync off, 4k60 is as smooth as butter and as sharp as 4k, much like OSX. It's nicer than Windows.