Power, Thermal And Acoustics; Power Management; Table 14. Power Management Features - Dell PowerEdge T20 Technical Manual

Power, thermal and acoustics

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Lower overall system-level power draw is a result of breakthrough system design. The Dell
PowerEdge T20 server maximizes performance per watt through a combination of power and
cooling, energy-efficient technologies and tools. Additionally, the PowerEdge T20 has an extensive
collection of sensors that automatically track thermal activity, which helps regulate temperature,
thereby reducing server noise and power consumption.

Power management

Table 14 summarizes power management features on the PowerEdge T20.
Feature
ACPI mode switch
Sleep states
Power button
Real-time clock (RTC)
Power management timer
Power management event
(PME)
DBS
C state support
Dell PowerEdge T20 Technical Guide
Table 14. Power management features
Enable/Status/Ctrl
Type
bit location
Fixed PCH
Fixed PCH
Fixed PCH
Fixed PCH
Fixed PCH
Generic PCH
N/A Processor MSRs
N/A Processor and PCH
registers
Description
The operating system uses the
SCI_EN bit in PCH to switch
from legacy mode to ACPI
mode.
Supported states: S0 (Working),
S4-OS ('Hibernation'), and S5
(Soft-off).
S1 (also called 'standby' or
'suspend') and S3 are not
supported.
In ACPI mode, the operating
system has control of the power
button. In non-ACPI mode, SMI
handler owns power button
events.
The operating system is able to
configure the system to wake on
the RTC alarm.
PCH 32-bit power management
timer is used.
When a device signals PME, the
system wakes (if necessary), the
OS detects the event, and a Dell-
defined ASL routine handles the
event. Wake-on-LAN is one
example of a PME.
This feature does P state
transition under Windows.
This feature allows multiple C
state support for the processor.
This feature will work under
Windows and ACPI OS that
understand C states.
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