I have an Asus G14 laptop (2020) with an nVidia 2060 GPU.
I have just done a clean install of Zorin 16 Core using the nVidia boot/install option.
Problem #1 is that there is no 60Hz display mode listed for my external 4K display. This display works just fine at 60Hz at both 4096x2160 (native for this display) and 3840x2160 in Windows 10 on the same laptop and HDMI cable. Additionally on my Macbook Pro (2017 with Intel IGPU) also displays correctly at 60Hz with the same HDMI cable. So I know the display, cable and laptop are capable of this configuration.
I have attempted to set a custom display mode from bash but this results in a blank display at 60Hz
Problem #2 (and perhaps this should be a different thread) is that with the external 4K display connected using the nVidia 470 (tested) driver the frame-rate of the desktop drops to very, very low, making the desktop unusable. If I switch to the X.Org Nouveau open source driver, this behavior goes away and the desktop perform as expected (albeit it still stuck at 30Hz --- see problem #1).
There are no issues with the laptop onboard display running and working, only with the external 4K display.
I have done some searching and have not seen these issues here on the forum. If anyone has experienced this or have suggestions it would be appreciated! I am really liking Zorin 16 so far and will switch to Pro if I can get this figured out.