User`s manual

Chapter 4: AMI BIOS
4-9
QPI L0s and L1
QuickPath Interconnect (QPI) offers three power states called L0, L0s and
L1:
L0 is a normal operational state where data and control packets can be
transmitted and received. All power management states are entered from
this state.
L0s is intended as a power saving state. It allows a link to quickly enter and
recover form a power saving state without going through recovery.
L1 is a power saving state that allows an additional power saving over L0s,
but with additional resume (wake-up) latency.
Select Enabled to activate QPI power saving (L0s and L1 are automatically
selected by the motherboard), select Disabled for normal operational state
without any power-saving function. The options are Disabled and Enabled.
Memory Frequency
Use this option to force the system memory to run at a different frequency
than the default frequency. The available options are Auto, Force DDR-800,
Force DDR-1066, and Force DDR-1333.
Memory Mode
The options are Independent, Channel Mirror, Lockstep and Sparing.
Independent - All DIMMs are available to the operating system.
Channel Mirror - The motherboard maintains two identical copies of all data
in memory for redundancy.
Lockstep - The motherboard uses two areas of memory to run the same set
of operations in parallel.
Sparing - Memory sparing occurs when on-demand inactive memory is au-
tomatically activated by the system to temporarily replace failed memory until
a service action can be performed (supported only on 2010 Intel® Core™
processor family based on the 32nm Intel® microarchitecture).
Demand Scrubbing
Demand Scrubbing is a process that allows the CPU to correct correctable
memory errors found on a memory module. When the CPU or I/O issues a
demand-read command, and the read data from memory turns out to be a
correctable error, the error is corrected and sent to the requestor (the original
source). Memory is updated as well. Select Enabled to use Demand Scrub-
bing for ECC memory correction. The options are Enabled and Disabled.