Arduino PWM Fan Control System

An intelligent PWM fan control system based on Arduino, featuring real-time RPM monitoring and GPU temperature-adaptive speed adjustment.

Core Features

Arduino Hardware Controller

• Precise PWM Control: 0-255 speed levels, supports 4-wire PWM fans
• Real-time RPM Monitoring: Hardware interrupt-driven tachometer detection
• Data Validation: CRC8 checksum ensures reliable serial communication
• Power-off Memory: EEPROM saves speed settings, automatically restores after power loss
• Watchdog Protection: Prevents system crashes, automatic recovery

Go Software Controller

• GPU Temperature Adaptive: Automatically adjusts fan speed based on NVIDIA GPU temperature
• Flexible Configuration: YAML config file for custom temperature curves
• Multiple Modes: Auto mode, manual mode, read-only mode, test mode

Hardware Connection

• Arduino Nano (ATmega328P)
• 4-wire PWM Fan
• Pin Configuration:
  • Pin 3: Fan TACH signal (interrupt input)
  • Pin 5: PWM output

Quick Start

Configuration File Example

fan_level:
  - temp: 20
    fan: 50
  - temp: 30
    fan: 150
  - temp: 35
    fan: 255
    
serial_port: /dev/ttyUSB0

Usage Examples

# Manually set fan speed
./gpu_fan_auto_control -fan 150

# Read current speed
./gpu_fan_auto_control -readonly

# Automatic temperature control
./gpu_fan_auto_control

# Test mode (doesn't actually change speed)
./gpu_fan_auto_control -dryrun

Communication Protocol

Request:  fanpwm:<speed>:<sequence>:<CRC8>
Response: fanpwm:<RPM>:<speed>

Future Improvements

• Fix RPM detection
• Real-time RPM logging to PC

Why This Project?

My GPU is a heavily modified GTX2080Ti 22GB, equipped with a dedicated water cooling system and three huge fans. These fans are not controlled by the motherboard, so by default, they always run at full speed which is extremely noisy. I wanted a software solution that could automatically and intelligently control the fan speed for improved comfort and flexibility.