MSI B450M-A PRO MAX AM4 Micro-ATX Motherboard - Manual (Page 15)

15
Overview of Components Overview of Components
CPU_FAN1, SYS_FAN1: Fan Connectors
PWM Mode fan connectors provide constant 12V output and adjust fan speed with
speed control signal. When you plug a 3-pin (Non-PWM) fan to a fan connector in
PWM mode, the fan speed will always maintain at 100%, which might create a lot of
noise.
Adjusting fan speed
You can adjust fan speed in BIOS > HARDWARE MONITOR .
There are gradient points of the fan speed that allow you to
adjust fan speed in relation to CPU temperature.
Default PWM Mode fan connector
PWM Mode pin definition
1 Ground 2 +12V
3 Sense 4 Speed Control Signal
1
SYS_FAN1
1
CPU_FAN1