Chapter 3 – AMI BIOS Setup 74Fanless Embedded Controller BOXER-6843-ADS3.4.4.1 Smart Fan Mode ConfigurationOptions SummaryCPU FAN Output Mode Output PWM mode(open drain)Optimal Default, Failsafe DefaultLinear Fan ApplicationOutput PWM mode(push pull)Output PWM mode (push pull) to control 4-wire fans. Linear fan application circuit tocontrol 3-wire fan speed by fan’s power terminal. Output PWM mode (open drain) tocontrol Intel 4-wire fans.CPU Fan Smart Fan Control Manual Duty ModeAuto Duty-Cycle Mode Optimal Default, Failsafe DefaultSmart Fan Mode Select.Temperature Source CPU Temperature Optimal Default, Failsafe DefaultSystem TemperatureSystem Temperature 2Select the monitored temperature source for this fan.