Asus P6TD Deluxe - Manual (Page 96)

3-24 Chapter 3: BIOS setup
A20M [Disabled]
Legacy OSes and APs may need A20M enabled.
Configuration options: [Disabled] [Enabled]
Intel(R) SpeedStep (TM) Tech [Enabled]
When set to [Disabled], the CPU runs at its default speed. When set to [Enabled],
the CPU speed is controlled by the operating system.
Configuration options: [Disabled] [Enabled]
Intel(R) TurboMode tech [Enabled]
Turbo mode allows processor cores to run faster than marked frequency in specific
condition.
Configuration options: [Disabled] [Enabled]
Intel(R) C-STATE Tech [Disabled]
The Intel ® C-State Technology allows the CPU to save more power under idle
mode. Enable this item only when you install a C-State Technology-supported
CPU.
Configuration options: [Disabled] [Enabled]
C State package limit setting [Auto]
This item appears only when you set the Intel(R) C-STATE Tech item to [Enabled].
We recommend that you set this item to [Auto] for BIOS to automatically detect the
C-State mode supported by your CPU.
Configuration options: [Auto] [C1] [C3] [C6] [C7]