This page describes how to run coreboot on the ASUS P5Q desktop board.


  • PCI slots
  • PCI-e slots
  • Onboard Ethernet
  • USB
  • Onboard sound card
  • PS/2 keyboard
  • All 4 DIMM slots
  • S3 suspend and resume
  • Red SATA ports
  • Fan control through the W83667HG chip
  • FireWire

Not working

  • PS/2 mouse support
  • PATA aka IDE (because of buggy IDE controller)
  • Fan profiles with Q-Fan
  • TPM module (support not implemented)


  • S/PDIF
  • CD Audio In
  • Floppy disk drive

Flashing coreboot

Type Value
Socketed flash Yes
Model MX25L8005
Size 1 MiB
Package Socketed DIP-8
Write protection No
Dual BIOS feature No
Internal flashing Yes

You can flash coreboot into your motherboard using this guide.


Northbridge Intel P45 (called x4x in coreboot code)
Southbridge Intel ICH10R (called i82801jx in coreboot code)
CPU (LGA775) Model f4x, f6x, 6fx, 1067x (Pentium 4, d, Core 2)
SuperIO Winbond W83667HG
Coprocessor No
Clockgen (CK505) ICS 9LPRS918JKLF

Controlling fans

With vendor firmware, the P5Q uses the ATK0110 ACPI device to control its fans according to the parameters configured in the BIOS setup menu. With coreboot, one can instead control the Super I/O directly as described in the kernel docs:

  • pwm1 controls fan1 (CHA_FAN1) and fan4 (CHA_FAN2)
  • pwm2 controls fan2 (CPU_FAN)
  • fan3 (PWR_FAN) cannot be controlled
  • temp1 (board) can be used to control fan1 and fan4
  • temp2 (CPU) can be used to control fan2

Manual fan speed

These commands set the chassis fans to a constant speed:

# Use PWM output
echo 1 >/sys/class/hwmon/hwmon2/pwm1_mode
# Set to manual mode
echo 1 >/sys/class/hwmon/hwmon2/pwm1_enable
# Set relative speed: 0 (stop) to 255 (full)
echo 150 >/sys/class/hwmon/hwmon2/pwm1

Automatic fan speed

The W83667HG can adjust fan speeds when things get too warm. These settings will control the chassis fans:

# Set to "Thermal Cruise" mode
echo 2 >/sys/class/hwmon/hwmon2/pwm1_enable
# Target temperature: 60°C
echo 60000 >/sys/class/hwmon/hwmon2/pwm1_target
# Minimum fan speed when spinning up
echo 135 >/sys/class/hwmon/hwmon2/pwm1_start_output
# Minimum fan speed when spinning down
echo 135 >/sys/class/hwmon/hwmon2/pwm1_stop_output
# Tolerance: 2°C
echo 2000 >/sys/class/hwmon/hwmon2/pwm1_tolerance
# Turn fans off after 600 seconds when below defined range
echo 600000 >/sys/class/hwmon/hwmon2/pwm1_stop_time

You can also control the CPU fan with similar rules:

# Switch to "Thermal Cruise" mode
echo 2 >/sys/class/hwmon/hwmon2/pwm2_enable
# Target temperature: 55°C
echo 55000 >/sys/class/hwmon/hwmon2/pwm2_target
# Minimum fan speed when spinning down
echo 50 >/sys/class/hwmon/hwmon2/pwm2_stop_output
# Rate of fan speed change
echo 50 >/sys/class/hwmon/hwmon2/pwm2_step_output
# Maximum fan speed
echo 200 >/sys/class/hwmon/hwmon2/pwm2_max_output
# Tolerance: 2°C
echo 2000 >/sys/class/hwmon/hwmon2/pwm1_tolerance