ASROCK B450D4U-V1L User Manual page 60

FAN 6
This allows you to set the front fan 6's speed. The default value is [Smart Fan].
Smart Fan Control
This allows you to set the Smart fan's level speed.
Smart Fan Duty Control
Smart Fan Duty x (x means 1 to 11 stage)
This allows you to set duty cycle for each stage.
Smart Fan Temp Control
Smart Fan Temp x (x means 1 to 11 stage)
This allows you to set temperature for each stage.
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