Ultrawide Flickering at 240hz (RESOLVED)

Like the title states. I was having an insane time tryiung to get 240hz to work correctly on my LG Ultragear+. When I ran it at 240hz I would get artifacting and weird rendering issues. Especially if I had something pinned to 1/2 the screen and moved around other windows. This was totally resolved if I went to 144hz… Well I didn’t pay for 144hz I payed for the full 240hz and damnit I’m getting it.

This issues been plaguing me in my sleep finally went though enough config changes and got it going.

Changed these

/etc/environment
Added
POWERDEVIL_NO_DDCUTIL=1

/etc/modprobe.d/nvidia.conf
Added
options nvidia NVreg_RegistryDwords=“EnableBrightnessControl=1”
options nvidia_drm modeset=1 fbdev=1

The artifacing and flicking are totally gone now with no issues. I have lost so much sleep trying to troubleshoot this issue and its finally resolved.

System Info:
NVIDIA-SMI 590.48.01 Driver Version: 590.48.01 CUDA Version: 13.1

Operating System: EndeavourOS
KDE Plasma Version: 6.6.0
KDE Frameworks Version: 6.23.0
Qt Version: 6.10.2
Kernel Version: 6.18.9-arch1-2 (64-bit)
Graphics Platform: Wayland
Processors: 32 × 13th Gen Intel® Core™ i9-13900K
Memory: 32 GiB of RAM (31.0 GiB usable)
Graphics Processor: NVIDIA GeForce RTX 4080 SUPER
Manufacturer: Micro-Star International Co., Ltd.
Product Name: MS-7D91
System Version: 4.0

Leaving this here as I had to do this again on another install. After Gsync is disabled.

Go to System Settings > Display and Monitor > Display Configuration.

  1. Select your 240Hz Monitor.
  2. Look for a setting called “Internal Color Processing” or “Color Rendering”.
  3. Change it from “Prefer Efficiency” to “Prefer Color Accuracy”.
  4. Click Apply.