Chapter 6: UEFI BIOS
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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.
This feature must be set to Disable to be able to configure the next two features.
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
.
Package C State Control
Package C State
This feature allows the user to set the limit on the C State package register. The options
are C0/C1 State, C2 State, C6 (Non Retention) State
,
C6 (Retention) State, No Limit,
and
Auto.
CPU T State Control
Software Controlled T-States
Use this feature to enable Software Controlled T-States. The options are Disable and
Enable
.
