I just started working at a big company where I got a HP ZBook running Ubuntu 16.04.6. Apparently, this machine has a (unnecessary) 4K display. When hooking it up via HDMI to a 1080p screen, two weird things happen:
The laptop (sceen) is lower than my external monitor, so I configured it to be lower in the Nvidia settings. However, this causes the top statusbar to become "misaligned". If I arrange the screens as next to each other, the problem goes away.1
The alt+tab window switcher is situated below the screens. This happens regardles of the settings I have in Nvidia settings. 2
I've also tried the open source driver but it is even worse, It creates graphical glitches everywhere.