On this page you will find some information and tips about the fan above the heatsink of the processor.

The fan that cools the Ryzen™ processor of the UDOO BOLT GEAR is a 5V powered fan with PWM signal speed management and is managed entirely by the board's Embedded Controller.

The full management of the fan settings described below is possible starting from BIOS/UEFI Firmware version 1.07.
Heads up! Please, always keep updated the BIOS/UEFI Firmware of your UDOO BOLT GEAR to have the latest features and bugfix available.

BIOS/UEFI Fan Settings

Here a detailed description of the fan settings and its default values.

  --> Embedded Controller
      --> Internal Fan settings

          Enhanced 3 wire RPM measurement        <Disabled>
          Automatic Temperature FAN Control      <Enabled>
            AC0 Temperature (C)                  <85>
            AC1 Temperature (C)                  <70>
            Temperature Hysteresis               5
            FAN Duty Cycle (%) Above AC1         35
            Speed change duration                0

Enhanced 3 wire RPM measurement refers to an algorithm necessary for the consistent reading of the current fan speed to respond to the tachometer signal. This data is made available by EAPI libraries. The algorithm set the speed fan to 100% for 100 milliseconds every 3 seconds. This is the standard way for the 3 wires fan to have a consistent reading of the speed. By default it is disabled because it can create a perceptible non-linear motion sound effect on some fans or some assembly situations.

AC0 Temperature indicates the temperature above which the fan start turns on at full 100% rotation speed.

AC1 Temperature indicates the temperature above which the fan start turns on at the % rotation speed indicated by the FAN Duty Cycle (%) Above AC1 value.

Temperature Hysteresis This value is added to AC0 and AC1 when temperature is growing and subtracted when it is lowering to avoid oscillation.

FAN Duty Cycle (%) Above AC1 is the percentage speed at which the fan turns when the processor's temperature is in the range between AC1 and AC0.

Speed change duration indicates the time with which the speed changes linearly from one speed value to another (it is a ramp in practice, if set to 0 the fan will start directly at the right speed, if other values are set the fan will start more slowly and arrive at the selected speed more gradually).

Info Preset values above are designed for a normal desktop working environment. These settings help minimize fan noise while keeping the system properly cooled in a normal working environment. The default settings may be modified in future BIOS revisions as UDOO continues to fine-tune them to get the best trade-off between cooling and fan acoustics.
You may need to change the fan settings if your usage model includes any of the following:

  • Heavy image/video processing or analysis.
  • Gaming, Stress testing or Benchmarking.
  • Sustained processor usage of 75% or higher, for a long period.

If you are in one of these usage scenarios, we suggest raising the value of FAN Duty Cycle % Above AC1 and lowering the AC1 Temperature and AC0 Temperature to maintain a lower processor operating temperature and be sure to always use maximum performance.

if the fan is changed to one that does not handle PWM rotation speed, it is important for proper fan operation to set the values for FAN Duty Cycle % Above AC1 to 100 and Speed change duration to 0.

This page was last updated on Wednesday, December 9, 2020 at 6:56 AM.