Nvidia 754 User Manual page 49

BIOS
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 Thunder Probe Software to tune your fan.
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