Owners Manual

Table Of Contents
Option Description
The options available are Maximum data rate, 10.4 GT/s, and 9.6 GT/s. This option is set to Maximum
data rate by default.
Maximum data rate indicates that the BIOS runs the communication links at the maximum frequency
supported by the processors. You can also select specific frequencies that the processors support, which
can vary.
For best performance, you should select Maximum data rate. Any reduction in the communication
link frequency affects the performance of non-local memory accesses and cache coherency traffic. In
addition, it can slow access to non-local I/O devices from a particular CPU.
However, if power saving considerations outweigh performance, you might want to reduce the frequency
of the CPU communication links. If you do this, you should localize memory and I/O accesses to the
nearest NUMA node to minimize the impact to system performance.
Virtualization
Technology
Enables or disables the virtualization technology for the processor. This option is set to Enabled by
default.
Adjacent Cache
Line Prefetch
Optimizes the system for applications that need high utilization of sequential memory access. This option
is set to Enabled by default. You can disable this option for applications that need high utilization of
random memory access.
Hardware
Prefetcher
Enables or disables the hardware prefetcher. This option is set to Enabled by default.
Software
Prefetcher
Enables or disables the software prefetcher. This option is set to Enabled by default.
DCU Streamer
Prefetcher
Enables or disables the Data Cache Unit (DCU) streamer prefetcher. This option is set to Enabled by
default.
DCU IP
Prefetcher
Enables or disables the Data Cache Unit (DCU) IP prefetcher. This option is set to Enabled by default.
Sub NUMA
Cluster
Enables or disables the Sub NUMA Cluster. This option is set to Disabled by default.
UPI Prefetch Enables you to get the memory read started early on DDR bus. The Ultra Path Interconnect (UPI) Rx path
will spawn the speculative memory read to Integrated Memory Controller (iMC) directly. This option is set
to Enabled by default.
Logical Processor
Idling
Enables you to improve the energy efficiency of a system. It uses the operating system core parking
algorithm and parks some of the logical processors in the system which in turn allows the corresponding
processor cores to transition into a lower power idle state. This option can only be enabled if the
operating system supports it. It is set to Disabled by default.
x2APIC Mode Enables or disables the x2APIC mode. This option is set to Disabled by default.
Dell Controlled
Turbo
Controls the turbo engagement. Enable this option only when System Profile is set to Disabled.
NOTE: Depending on the number of installed CPUs, there might be up to two processor listings.
Number of Cores
per Processor
Controls the number of enabled cores in each processor. This option is set to All by default.
Processor Core
Speed
Specifies the maximum core frequency of the processor.
Processor n
NOTE: Depending on the number of CPUs, there might be up to two processors listed.
The following settings are displayed for each processor installed in the system:
Option Description
Family-Model-
Stepping
Specifies the family, model, and stepping of the processor as defined by Intel.
Brand Specifies the brand name.
Level 2 Cache Specifies the total L2 cache.
Pre-operating system management applications 29