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║ CAGT — AMD GPU Fan Control ║
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CAGT

A single-file, TUI AMD GPU fan controller for Linux
Just you and your GPU cooled properly.

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What is CAGT?

CAGT is a single C file, TUI-based fan controller for AMD GPUs on Linux.

It reads your GPU temperature directly from hwmon, runs it through a fan curve, and writes the correct PWM value. It also runs as a background daemon with a clean CLI for remote control.

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Quick Start

gcc -std=c99 -O2 -o cagt cagt.c -lncurses
chmod +x cagt
sudo ./cagt

For daemon mode (example):

sudo ./cagt --daemon
./cagt status
./cagt fan 75
./cagt quit

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Development

If you're modifying CAGT, compile with stricter warnings to catch issues early:

gcc -std=c99 -O2 -Wall -Wextra -Wpedantic -Wanalyzer-file-leak -o cagt cagt.c -lncurses

The production build doesn't need these flags, but they help catch bugs during development.

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TUI Controls

Key	Action
1 – 9	Select GPU (multi-GPU systems)
M	Toggle Manual / Auto mode
T	Cycle temperature unit (°C → °F → K)
S	Cycle temp sensor (Edge / Junction / Memory)
C	Cycle fan curve (Default / Quiet / Aggressive / Linear / Custom)
R	Reset peak temperature
+ / -	Adjust fan by ±5% (enters Manual)
↑ / ↓	Adjust fan by ±1% (enters Manual)
0	Set fan to 0% instantly
Q	Quit (restores auto fan control)

All manual adjustments auto-switch you into Manual mode. Press M to go back to the curve.

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Daemon CLI

Command	Action
cagt status	Show current temperature, fan speed, RPM, and mode
cagt gpu <1-N>	Select active GPU (multi-GPU systems)
cagt fan <0-100>	Set manual fan speed
cagt fan auto	CAGT controls fan via curve
cagt fan gpu	GPU hardware controls fan
cagt curve <name|0-4>	Select curve (default, quiet, aggressive, linear, custom)
cagt curve list	List available curves
cagt log <interval>	Set logging interval (1s, 5s, 10s, 500ms, off)
cagt quit	Stop daemon

The daemon forks to the background on start. It communicates via a Unix socket. If the daemon is running and you launch cagt without arguments, it will tell you. If the daemon is not running and you use a command, it will tell you to start it.

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Features

• Clean ncurses TUI — color-coded temps, fan curve visualization, RPM display
• Background daemon mode with Unix socket CLI
• Multi-GPU support — tabbed title bar, per-GPU independent state
• 5 fan curves — Default, Quiet, Aggressive, Linear, and Custom
• Custom fan curves via config file (~/.config/cagt/custom_curve.conf)
• Multi-sensor — Edge, Junction, Memory temperature where available
• Manual override — granular 1% or 5% steps, plus instant presets
• Temperature units — Celsius, Fahrenheit, or Kelvin
• Peak temperature tracking with reset
• Zero RPM detection
• Runtime counter
• Optional CSV logging (--log flag)
• Persistent settings per GPU (saved to ~/.config/cagt/config.conf)
• RDNA3 fan_curve interface support
• ppfeaturemask detection with specific RDNA3 warnings
• Safe exit with verified auto-restore — handles known pwm1_enable quirks
• 25+ GPU detection — Polaris, Vega, Navi, RDNA3, and older GCN
• Single file — no headers, no build system, no dependencies beyond ncurses

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Custom Fan Curve

Create ~/.config/cagt/custom_curve.conf:

# Format: temperature_c fan_percent
20 0
40 20
55 35
65 50
75 70
85 90
100 100

At least 2 points required. Temperatures must be ascending. Select it with cagt curve custom or cycle to it in the TUI with C.

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Default Fan Curve

Temp (°C)	Fan Speed
20	0%
35	20%
50	30%
60	45%
70	60%
80	75%
90	90%
100	100%

Also available: Quiet, Aggressive, and Linear curves. Temperatures between points are linearly interpolated.

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Supported GPUs

Generation	Models
Polaris	RX 560, RX 570, RX 580 (including 2048SP)
Vega	RX Vega 56, Vega 64, Radeon VII
Navi 10	RX 5600 XT, RX 5700, RX 5700 XT
Navi 20	RX 6700 XT, RX 6800, RX 6800 XT, RX 6900 XT
Navi 30 (RDNA3)	RX 7600, RX 7700 XT, RX 7800 XT, RX 7900 XT, RX 7900 XTX
Older GCN	HD 7950, HD 7970, R9 290/390, R9 Fury

Unknown AMD GPUs still work, they just show their PCI device ID.

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RDNA3 Requirements

RDNA3 GPUs (RX 7000 series) require the amdgpu overdrive bit to be enabled for manual fan control. If you see a warning about ppfeaturemask, add this to your kernel cmdline or /etc/modprobe.d/amdgpu.conf:

amdgpu.ppfeaturemask=0xffffffff

Then reboot.

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Dependencies

CAGT requires only ncurses for its TUI.

# Artix / Arch
sudo pacman -S ncurses

# Debian / Ubuntu
sudo apt install libncurses-dev

# Fedora
sudo dnf install ncurses-devel

# Void
sudo xbps-install ncurses-devel

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Project Structure

CAGT/
├── cagt.c           # the entire program
├── LICENSE          # IRX License 1.0
├── CONTRIBUTING     # contribution guidelines
└── README.md        # this file

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Why CAGT Exists

CAGT is a small personal project.

It's a single static binary that runs in your terminal or as a daemon, updates at 10Hz, and exits cleanly, restoring your GPU to automatic control every time.

Do one thing and do it well.

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Contributing

Contributions welcome.

Keep it simple. CAGT is intentionally a single-file tool with no external dependencies beyond ncurses.

Please read CONTRIBUTING for guidelines.

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License

Licensed under the IRX License 1.0 © realvolk 2026.