Cpu_Fan1~2,Sys_Fan1~4: Fan Connectors - MSI B250M BAZOOKA User Manual

CPU_FAN1~2,SYS_FAN1~4: Fan Connectors

Fan connectors can be classified as PWM (Pulse Width Modulation) Mode and DC
Mode. PWM Mode fan connectors provide constant 12V output and adjust fan speed
with speed control signal. DC Mode fan connectors control fan speed by changing
voltage. When you plug a 3-pin (Non-PWM) fan to a PWM Mode fan connector, the fan
speed will be always maintained at 100%, and that could be noisy.
Switching fan mode and adjusting fan speed
You can switch between PWM mode and DC mode and adjust fan speed in BIOS >
Advanced > Hardware Monitor.
Select PWM Mode or DC Mode
In Hardware Monitor sub-menu, you can set the temperature levels and the
corresponding fan speed levels.
Important
Make sure fans are working properly after switching the PWM/ DC mode.
PWM Mode fan connector
1 Ground
3 Sense
DC Mode fan connector
1
SYS_FAN1
1 Ground
3 Sense
1
CPU_FAN1
2 +12V
4 Speed Control Signal
1
SYS_FAN2
2 Voltage Control
4 NC
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