Power Management Features; Acpi; Fan Connectors; Fan Speed Control (Intel ® Precision Cooling Technology) - Intel D925XEBC2 Product Manual

Power Management Features

Power management is implemented at several levels, including:
•
Advanced Configuration and Power Interface (ACPI)
•
Hardware support:
⎯ Fan connectors
⎯ Suspend to RAM (Instantly Available PC technology)
⎯ Resume on Ring
⎯ Wake from USB
⎯ Wake from PS/2 keyboard/mouse

ACPI

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.

Fan Connectors

Desktop Board D925XECV2 has three chassis fan headers (two 3-pin and one 4-pin) and one
processor fan header (4-pin).
Desktop Board D925XEBC2 has two chassis fan headers (3-pin) and one processor fan header
(4-pin).
See Figure 25 on page 49 for the location of the fan headers.
Fan Speed Control (Intel
Intel Precision Cooling Technology automatically adjusts the processor fan speed based on the
processor temperature and adjusts the chassis fan speeds depending on the system temperature.
System fan noise may be reduced by operating controlled chassis and processor fans at the
minimum necessary speeds.
NOTE
Not all chassis fan headers on Desktop Board D925XECV2 are controlled. Refer to Table 2 on
page 12 to identify controlled chassis fan headers.
The processor and chassis fan speed control features can be disabled independently through the
desktop board BIOS. Disabling the processor fan speed control will result in the fan operating at
full speed if it is not a self controlled fan. It is recommended that processor fan speed control
remain enabled (default BIOS setting) when using the processor fan heat-sink included with Intel
boxed processors. Disabling the chassis fan speed control results in chassis fans always operating
at full speed. The chassis fan speed control feature should be disabled if a self-controlled chassis
fan is attached to any controlled chassis fan header.
The overall system noise reduction will vary based on system configuration and environment.
®
Precision Cooling Technology)
Desktop Board Features
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