Chapter 4: BIOS
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EIST PSD Funtion
This feature allows the user to choose between Hardware and Software to control the
processor's frequency and performance (P-state). In HW_ALL mode, the processor hard-
ware is responsible for coordinating the P-state, and the OS is responsible for keeping the
P-state request up to date on all Logical Processors. In SW_ALL mode, the OS Power
Manager is responsible for coordinating the P-state, and must initiate the transition on
all Logical Processors. In SW_ANY mode, the OS Power Manager is responsible for
coordinating the P-state and may initiate the transition on any Logical Processors. The
options are
HW_ALL
, SW_ALL, and SW_ANY.
Turbo Mode
This feature will enable dynamic control of the processor, allowing it to run above stock
frequency. The options are Disable and
Enable
.
Hardware PM State Control
Hardware P-States
This setting allows the user to select between OS and hardware-controlled P-states.
Selecting Native Mode allows the OS to choose a P-state. Selecting Out of Band Mode
allows the hardware to autonomously choose a P-state without OS guidance. Selecting
Native Mode with No Legacy Support functions as Native Mode with no support for older
hardware. The options are
Disable
, Native Mode, Out of Band Mode, and Native Mode
with No Legacy Support.
CPU C State Control
Autonomous Core C-State
Enabling this setting allows the hardware to autonomously choose to enter a C-state
based on power consumption and clock speed. The options are
Disable
and Enable.
CPU C6 Report
Select Enable to allow the BIOS to report the CPU C6 State (ACPI C3) to the operating
system. During the CPU C6 State, the power to all cache is turned off. The options are
Disable, Enable, and
Auto
.
Enhanced Halt State (C1E)
Select Enable to use Enhanced Halt State technology, which will significantly reduce the
CPU's power consumption by reducing its clock cycle and voltage during a Halt state.
The options are Disable and
Enable
.
