Hello, I’ve been trying to deal with a certain color banding issues with both the ASUS XG27UQ and VG278Q monitors. I’ve realized this issue at first when I was trying to learn how to digitally paint in Clip Studio Paint, specifically shading, mixing colors and bluring. Every time I use their standard soft brush, air brush, gradient or blur tools, it would always give out those un wanted streaks/lines. I thought maybe it was just Clip studio paint itself but as I research more for help, I’ve noticed color banding on my desktop inside windows 11 as well, even when I was using Arch linux and windows 10. I have attached 3 images, one showing the problem on steam, one showing on a youtube video, and lastly a screenshot of what the lagom gradient test image looks like on my monitor.

I also checked the nvidia settings as well and my monitors were using the highest (32-bit) Desktop Color Depth, stuck with 8 bit Output Color Depth and are running at 144Hz Refresh rate. The 2 VG278Q are using RGB Output Color Format and Full Output Dynamic Range, while the XG27UQ monitor can only use YCbCr 4:2:2 Output Color Format and Limited Output Dynamic Range, though if I lower that down to 60Hz, then I can use RGB and increase the Output Color Depth to 10. Changing around these settings AND adjusting the settings in the monitors OSD made no difference with the color banding issue though setting the XG27UQ to 60HZ and using RGB Full reduce it only slightly, the vertical banding on the lagom test image is still there. Using different ICC profiles only changed the colors slightly, which made me think I should buy a colorimeter to improve the colors, also trying to change the settings through Calibration Tools and screwing around with the gamma, but once again did not help with the color banding issues whatsoever. The last thing I’ve tried was trying to enable Dithering with 8 bit temporal, 10 bit temporal and 8 bit 2×2 dynamic reg keys from the sticky thread here, nothing changed yet again. Yesterday I also played around the Arch Linux OS and the color banding still came up.

I have also attempted to reinstall windows 10, uninstall and clean install the Nvidia drivers, disabled the windowscolorsystem task scheduler, used calibration tools as well, trying to change the gamma in general and/or each R.G.B sliders, it did not make a difference either. I can't tell if this is due to my GPU, the monitor itself or the displayport cable that came with the monitors. I also tested this on an HP xi 25" IPS monitor and its giving out the same banding issues too. no differences on there compared to the ASUS monitors.

So the reason I’m posting here is because I want to see if anyone can get help to troubleshoot this if this is a software/OS issue, I’m wondering if buying a colorimeter and calibrating it would finally fixed the issue, or if I have to actually contact ASUS and RMA all the monitors. I want to get some insight first before I spend money.

and my setup is:
CPU: intel i7-7700K
GPU: Nvidia GTX 1070 EVGA FTW with triple monitor set up of 2 VG278Qs and a XG27UQ monitor
Motherboard: ASUS Prime z270-K
RAM: 16GB
OS: Windows 10 (also tested on Windows 11 and Arch Linux too)