Intel DQ57TM User Manual

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Power management is implemented at several levels, including software support 
through the Advanced Configuration and Power Interface (ACPI) and the following 
hardware support: 
•  Power connectors 
•  Fan headers 
•  LAN wake capabilities 
•  Instantly Available PC technology (Suspend to RAM) 
•  +5 V standby power indicator LED 
•  Wake from USB 
•  PCI Power Management Event signal (PME#) wakeup support 
•  PCI Express WAKE# signal support 
•  Wake from PS/2 devices 
•  Wake from serial port 

ACPI gives the operating system direct control over the power management and Plug 
and Play functions of a computer.  The use of ACPI with the Desktop Board requires an 
operating system that provides full ACPI support. 

ATX12V-compliant power supplies can turn off the computer power through system 
control.  When an ACPI-enabled computer receives the correct command, the power 
supply removes all non-standby voltages. 

When resuming from an AC power failure, the computer returns to the power state it 
was in before power was interrupted (either on or off).  The computer’s response can 
be set by using the Last Power State feature in the BIOS Setup program’s Boot menu. 

The Desktop Board has two power connectors.  See Figure 26 on page 58 for the 
location of the power connectors. 

The function/operation of the fans is as follows: 
•  The fans are on when the board is in the ACPI S0 or S1 state. 
•  The fans are off when the computer is in the ACPI S3, S4, or S5 state. 
•  Each fan header is wired to a tachometer input. 
•  All fan headers support closed-loop fan control that can adjust the fan speed or 

switch the fan on or off as needed. 

•  All fan headers have a +12 V DC connection. 
•  All fan headers are controlled by Pulse Width Modulation. 
•  The front and rear chassis fans support Linear Fan Control on 3-wire fans.