Asus P4B533-VM - Manual (Page 90)

4-30 Chapter 4: BIOS Setup
4.5.2 Hardware Monitor
CPU Q-Fan Function [Disabled]
This item allows you to enable or disable the ASUS Q-Fan feature that
smartly adjusts the fan speeds for more efficient system operation. When
this field is set to [Enabled], the CPU Temperature Threshold and CPU
Fan Lowest Level Voltage items appear. Configuration options:
[Disabled] [Enabled]
CPU Temperature Threshold
This item allows you to set the highest temperature for the CPU so that
when exceeded by the actual CPU temperature, Q-Fan supplies more
power to the CPU fan. When the CPU temperature goes below the setting,
Q-Fan automatically reverts to the normal power supplied to the fan.
Configuration options: [50°C] [55°C] [60°C] [65°C] [70°C]
CPU Fan Lowest Level Voltage
This item allows you to set the lowest voltage applied to the CPU fan.
Configuration options: [6V] [6.5V] [7V] [7.5] [8V] [8.5] [9V]