DDC/CI: Debian Setup

This repository contains Shell scripts which automatically install packages required to run DDC/CI software for NVIDIA GPU. DDC/CI packages introduced in this repository are as follows:

• ddccontrol
  • Exclusive to Debian 9 "stretch"
• ddcutil
  • Available on Debian 9 "stretch" and 10 "buster"

As mentioned above, this repository focuses DDC/CI on NVIDIA graphic card; the Shell scripts does not have graphic card detection, thus should not be used on AMD.

Changing Linux Repository

Reference: https://wiki.debian.org/NvidiaGraphicsDrivers/

To install NVIDIA graphic packages to Debian distribution, new components needs to be added on Linux repository located in /etc/apt/sources.list; change the component from main to main contrib non-free and update repository.

$ sudo apt update

NVIDIA Configuration

Reference: http://www.ddcutil.com/nvidia/

Depending on NVIDIA graphic card, there may require additional modification on NVIDIA parameters. Copy /usr/share/X11/xorg.conf.d/ directory to /etc/X11 and modify 90-nvidia_i2c.conf file as shown below:

Section "Device"
    Driver        "nvidia"
    Identifier    "Dev0"
    Option        "RegistryDwords" "RMUseSwI2c=0x01; RMI2cSpeed=100"
    # solves problem of i2c errors with nvidia driver
    # per https://devtalk.nvidia.com/default/topic/572292/-solved-does-gddccontrol-work-for-anyone-here-nvidia-i2c-monitor-display-ddc/#4309293
EndSection

This changes the NVIDIA parameter setting on I2C switching and and speed options.

Additionally, add the following code to /etc/modprobe.d/nvidia-kernel-common.conf file which is about NVIDIA kernel related Linux modules.

options nvidia NVreg_RegistryDwords=RMUseSwI2c=0x01;RMI2cSpeed=100