Asus CM1740 User Manual page 59

From the Monitor menu, select Clean Level and press <Enter> to display its
3.
configuration options.
Select your preferred option from Clean Level's four configuration options:
4.
• Disable: Disables the fan system and the fan operates under the Q-Fan settings.
• Silent: 40% of the fan's performance (poor performance but low noise)
• Optimal: 70% of the fan's performance (standard setting).
• Performance: Fan's full performance (best performance but noisy)
Press <F10> and click Yes to save your settings. The system automatically reboots to
5.
finish the setup process.
During the system reboot, the Power LED flashes to indicate that the dust extraction fan
rotates in reverse to remove the dust from the internal system components.
ASUS CM1740 59