Chapter 4: AMI BIOS
4-7
Execute-Disable Bit Capability (Available if supported by the OS & the CPU)
Select Enabled to enable the Execute-Disable Bit which will allow the processor
to designate areas in the system memory where an application code can execute
and where it cannot, thus preventing a worm or a virus from flooding illegal codes
to overwhelm the processor or damage the system during an attack. The default is
Enabled
. (Refer to Intel and Microsoft Web sites for more information.)
PPIN Control
Select Enable to unlock the PPIN control. The options are
Enabled
and Disabled.
Hardware Prefetcher (Available when supported by the CPU)
If set to Enabled, the hardware prefetcher will prefetch streams of data and instruc-
tions from the main memory to the L2 cache to improve CPU performance. The
options are Disabled and
Enabled
.
Adjacent Cache Line Prefetch (Available when supported by the CPU)
The CPU prefetches the cache line for 64 bytes if this feature is set to Disabled.
The CPU prefetches both cache lines for 128 bytes as comprised if this feature is
set to
Enabled
.
DCU Streamer Prefetcher (Available when supported by the CPU)
Select Enabled to enable the DCU (Data Cache Unit) Streamer Prefetcher which
will stream and prefetch data and send it to the Level 1 data cache to improve
data processing and system performance. The options are Disabled and
Enabled
.
DCU IP Prefetcher (Available when supported by the CPU)
Select Enabled for DCU (Data Cache Unit) IP Prefetcher support, which will prefetch
IP addresses to improve network connectivity and system performance. The options
are Disabled and
Enabled
.
Direct Cache Access (DCA Support)
Select Enabled to use Intel's DCA (Direct Cache Access) Technology to improve
data transfer efficiency. The options are
Enabled
and Disabled.
X2APIC
Select Enable to activate APIC (Advanced Programmable Interrupt Controller) sup-
port. The options are
Enabled
and Disabled.
AES-NI
Select Enable to use the Intel Advanced Encryption Standard (AES) New Instruc-
tions (NI) to ensure data security. The options are
Enabled
and Disabled.
