Asus M2N-SLI - Manual (Page 136)

-22 Chapter : Software support
You can also set the AI Gear modes by clicking the AI Gear icon on the Windows
taskbar.
• When AI Gear is enabled, the system will automatically optimize the CPU
and chassis fan speed according to the system loading.
• The AI Booster (AI NOS) and AI Gear functions cannot be enabled
simultaneously.