Asus P4B533 - Manual (Page 19)

ASUS P4B533 motherboard user guide 1-5
Dual function power switch
While the system is ON, pressing the power switch for less than 4 seconds
puts the system to sleep mode or to soft-off mode, depending on the BIOS
setting. Pressing the power switch for more than 4 seconds lets the
system enter the soft-off mode regardless of the BIOS setting.
ACPI ready
The Advanced Configuration power Interface (ACPI) provides more energy
saving features for operating systems that support OS Direct Power
Management (OSPM).
Auto fan off
The system fans power off automatically when the system is in sleep
mode. This feature reduces both power consumption and system noise.
Chassis intrusion detection
The motherboard supports chassis intrusion monitoring through the ASUS
ASIC. A chassis intrusion event is retained in the system memory for more
protection.