Hyper-threading, Active processor core, Limit cpuid maximum – ADLINK aTCA-6200A User Manual
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Hyper-threading
This item allows you to enable or disable the Hyper-Threading technology. Options:
Enabled/Disabled.
Active Processor Core
This item allows you to select the number of cores to enable in each processor package. This
BIOS setting is present only when a multi-core processor is installed.
Limit CPUID Maximum
When the computer is booted up, the operating system executes CPUID instruction to
identify the processor and its capabilities. Before it can do so, it must first query the
processor to find out the highest input value CPUID recognizes. This determines the kind of
basic information CPUID can provide the operating system. This option allows you to
circumvent problems with older operating systems that do not support Intel Pentium 4
processor with Hyper-Threading Technology.
When Enabled, the processor will limit the maximum CPUID input value to 03h when
queried, even if the processor supports a higher CPUID input value. When Disabled, the
processor will return the actual maximum CPUID input value of the processor when queried.
Options: Enabled/Disabled.
Execute Disable Bit
Intel’s Execute Disable Bit functionality can help prevent certain classes of malicious buffer
overflow attacks when combined with a supporting operating system. Execute Disable Bit
allows the processor to classify areas in memory by where application code can execute and
where it cannot. When a malicious worm attempts to insert code in the buffer, the
processor disables code execution and prevents damage and worm propagation.
Hardware Prefetcher
This is used for reducing the waiting time of DRAM. The hardware prefetcher looks for
streams of data and tries to predict what data will be needed next by the processor and
proactively tries to fetch these data. Options: Enabled/Disabled.
Adjacent Cache Line P
It is opened for choose the optimal use of sequential memory access for performance
purpose. Disable this setting for the application that requires high use of random memory
access. Options: Enabled/Disabled.