Processor Settings - IBM x3850 X6 Planning And Implementation Manual

5.3.2 Processor settings

Processor settings control the various performance and power features that are available on
the installed Xeon processor.
Figure 5-16 shows the UEFI Processor system settings window with the default values.
Figure 5-16 UEFI Processor system settings panel
The following processor feature options are available:
Turbo Mode (Default: Enabled):
This mode enables the processor to increase its clock speed dynamically as long as the
CPU does not exceed the Thermal Design Power (TDP) for which it was designed. See
"Turbo Boost Technology 2.0" on page 26, for additional information about Intel Turbo
Boost.
Processor Performance States (Default: Enabled):
This option enables Intel Enhanced SpeedStep Technology that controls dynamic
processor frequency and voltage changes, depending on operation.
CPU C-States (Default: Enabled):
This option enables dynamic processor frequency and voltage changes in the idle state,
providing potentially better power savings.
Package ACPI C-State Limit (Default: ACPI C3):
The Advanced Configuration and Power Interface (ACPI) is configured as ACPI C3 by
default.
C1 Enhanced Mode (Default: Enabled):
This option enables processor cores to enter an enhanced halt state to lower the voltage
requirement, and it provides better power savings.
Hyper-Threading (Default: Enabled):
This option enables logical multithreading in the processor, so that the operating system
can execute two threads simultaneously for each physical core. See "Hyper-Threading
Technology" on page 25 for more information.
Execute Disable Bit (Default: Enabled):
This option enables the processor to disable the execution of certain memory areas,
therefore preventing buffer overflow attacks.
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