Nuclear Fan Control V2 for ASUS G14

Advanced fan and thermal management script for ASUS G14 laptops with NVIDIA RTX 2060 Max-Q.

Features

• GPU Runtime Power Management: Automatically removes problematic NVIDIA USB controller to allow GPU suspend
• Multi-layered thermal control: Temperature-based throttle policy management
• CPU frequency capping: Prevents unnecessary boost to reduce heat
• Stuck fan detection: Automatic firmware reset when fans don't respond
• Wake event monitoring: Logs and responds to GPU wake events

Critical Fix: NVIDIA USB Controller Issue

The Problem

The NVIDIA USB 3.1 Host Controller (PCI device 0000:01:00.2) has a runtime power management bug that prevents it from suspending:

• Kernel error: xHCI save state timeout
• Runtime status stuck in "error" state
• Blocks parent GPU (0000:01:00.0) from entering D3 suspend state
• Results in: GPU stays active, fans spin up, higher temps and power consumption

The Solution

On startup, the script automatically removes the problematic USB controller device:

echo "1" > /sys/bus/pci/devices/0000:01:00.2/remove

Why this is safe:

• The NVIDIA USB controller (Bus 001/002) has no devices connected
• All actual USB devices (keyboard, mouse, storage, Bluetooth) use the AMD controller
• Change is temporary - device returns after reboot
• GPU can now properly suspend, reducing temps by ~5-10°C and quieting fans

Installation

1. Copy nuclear-fan-control-v2.sh to /home/<user>/
2. Make executable: chmod +x nuclear-fan-control-v2.sh
3. Create systemd service file at /etc/systemd/system/aggressive-fan-control.service:

   [Unit]
   Description=Nuclear Fan Control V2 for ASUS G14
   After=multi-user.target systemd-modules-load.service
   StartLimitIntervalSec=0
   
   [Service]
   Type=simple
   ExecStart=/home/eric/nuclear-fan-control-v2.sh
   Restart=always
   RestartSec=5
   User=root
   StandardOutput=journal
   StandardError=journal
   
   # NOTE: Do NOT add WatchdogSec - script doesn't send watchdog signals
   # Adding it will cause service to crash every 30 seconds
   
   [Install]
   WantedBy=multi-user.target

4. Enable and start service:

   sudo systemctl daemon-reload
   sudo systemctl enable aggressive-fan-control.service
   sudo systemctl start aggressive-fan-control.service

Thermal Policies

• < 60°C: Quiet mode (throttle_policy=2)
• 60-75°C: Quiet/Balanced hybrid (based on fan speed)
• > 75°C: Performance mode (throttle_policy=1)

CPU Frequency Control

• < 70°C: Max frequency capped at 2.1GHz
• > 70°C: Full frequency range available (up to 4.5GHz)

Monitoring

Check service status and logs:

systemctl status aggressive-fan-control.service
journalctl -u aggressive-fan-control.service -f

Check GPU suspend state:

cat /sys/bus/pci/devices/0000:01:00.0/power/runtime_status

Troubleshooting

Service crashing with watchdog timeout (CRITICAL):

• Symptom: Service restarts every ~30 seconds, fans gradually spin up, core dumps accumulating
• Cause: WatchdogSec=30 in service file requires systemd-notify calls, which this script doesn't implement
• Fix: Remove the WatchdogSec=30 line from /etc/systemd/system/aggressive-fan-control.service
• Verify fix:

  journalctl -u aggressive-fan-control.service --since "1 hour ago" | grep watchdog
  ls /var/lib/systemd/coredump/core.nuclear* | wc -l  # Should not increase over time

• Note: The service file template below has this issue pre-fixed

GPU won't suspend:

• Check if NVIDIA USB controller is present: lspci -s 01:00.2
• Manually remove: echo "1" | sudo tee /sys/bus/pci/devices/0000:01:00.2/remove
• Verify GPU suspended: cat /sys/bus/pci/devices/0000:01:00.0/power/runtime_status

Fans still loud:

• Check CPU temperature: sensors | grep Tctl
• Verify throttle policy: cat /sys/devices/platform/asus-nb-wmi/throttle_thermal_policy
• Check platform profile: cat /sys/firmware/acpi/platform_profile
• Check for service crashes: systemctl status aggressive-fan-control.service

System Requirements

• ASUS G14 (2020) with NVIDIA RTX 2060 Max-Q
• Linux kernel with runtime PM support
• lm-sensors installed
• systemd

License

This script is provided as-is for personal use.