Intel i915PL User Manual page 45

SmartFan Function
Scroll to SmartFan Function and press <Enter>. The following screen appears:
Smart CPU FAN Function
This item selects how the fan speed should be set. Full speed fixes fan speed at100%
duty cycle. Control the Fan by Duty-Cycle directly. By Temperature calculates the
fan speed according to different temperature range.
To use By Temperature setting, refer to the example below to set the temperature
and duty cycle.
Current CPU Temperature/Fan Speed
Display the current CPU Temperature/Fan speed.
Smart Fan example:
Only need to set the items in gray. The system will automatically
calculate intermediate temperature Temp LM and Temp MH and the
corresponding Duty LM and Duty MH.
How effective Smart CPU Fan is will depend on fan design. Most
fans have built-in thermistor and may self adjust its speed. Some
fans have very limited duty cycle range open to fan control.
For best results use the bundled USDM Software to tune your fan.
BIOS
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