nvfancontrol

Introduction
Getting started
- On Linux
- On Windows
Bugs
License

Introduction

Nvfancontrol provides dynamic fan control for NVidia graphic cards on Linux and Windows.

Sometimes it is desirable to control the fan speed of the graphics card using a custom response curve instead of the automatic setting that is built into the card’s BIOS. Especially in newer GPUs the fan does not kick in below 60°C or a certain level of GPU utilization. This is a small toy project in Rust to achieve a more elaborate control over this using either XNVCtrl in Linux or NVAPI in Windows. It is a work in progress so proceed with caution!

The minimum supported driver version is 352.09. The program currently supports single GPU configurations.

Getting started

The easiest way to get started is to download one of the available releases on github. For Archlinux there is also an AUR package available. The latest stable release is 0.3.0. If you are feeling adventurous and you want to compile it from scratch or want to hack around you might want to follow the relevant instructions for your operating system.

On Linux (and possibly FreeBSD)

Required libraries: Xlib, Xext and the proprietary NVidia driver, version 352.09 or newer

You must enable Coolbits to expose the manual fan adjustment feature. To do so create a file named 20-nvidia.conf within /etc/X11/xorg.conf.d/ or /usr/share/X11/xorg.conf.d/ (depends on your distribution) containing the following

Section "Device"
    Identifier "Device 0"
    Driver     "nvidia"
    VendorName "NVIDIA Corporation"
    BoardName  "IDENTIFIER FOR YOUR GPU"
    Option     "Coolbits" "4"
EndSection

The important bit is the Coolbits option. Valid Coolbits values for dynamic fan control are 4, 5 and 12. A sample configuration file is provided with the release tarball.

On Windows

nvfancontrol should work without further dependencies on Windows 7 or newer. Just make sure you have a recent NVidia driver and you should be good to go!

Use and configure

To run the program just execute the nvfancontrol binary. Add the -d or --debug argument for more output. To add a custom curve you can provide a custom configuration file. On Linux create a file named nvfancontrol.conf under the XDG configuration directory (~/.config or /etc/xdg for per-user and system-wide basis respectively). On Windows create the file in C:\Users\[USERNAME]\. The configuration file should contain pairs of whitespace delimited parameters (Temperature degrees Celsius, Fan Speed %). For example

Lines starting with # are ignored. You need at least two pairs of values.

Bear in mind that for most GPUs the fan speed can’t be below 20% or above 80% when in manual control, even if you use greater values. However, since these limits are arbitrary and vary among different VGA BIOS you can override it using the -l, or --limits option. For example to change the limits to 10% and 90% pass -l 10,90. To disable the limits effectively enabling the whole range just pass -l 0. In addition note that the program by default will not use the custom curve if the fan is already spinning in automatic control. This is the most conservative configuration for GPUs that turn their fans off below a certain temperature threshold. If you want to always use the custom curve pass the additional -f or --force argument. To terminate nvfancontrol send a SIGINT or SIGTERM on Linux or hit Ctrl-C in the console window on Windows.

Bugs

Although nvfancontrol should work with most Fermi or newer NVidia cards it has been tested with only a handful of GPUs. So it is quite possible that bugs or unexpected behaviour might surface. In that case please open an issue in the bug tracker including the complete program output (use the --debug option).