ASUS ProArt PA 248q flicker issue under linux

Monitor ASUS ProArt PA 248q has flickering issues when displaying some colors, like 30% grey.

Issue observed on Fedora 29/30/31, with nouveau driver for GE Force graphics card (GeForce GTX 980 Ti)

The issue is RESOLVED by changing the “nouveau” driver by the proprietary NVIDIA driver (version 440.36, released 22 Nov 2019).