IBM G52-72361X2 3-11, BIOS Setup Max CPUID Value Limit, Execute Disable Bit, Hardware Prefetcher

BIOS Setup

Max CPUID Value Limit

When CPUID instruction is executed, newer CPU may return a value greater than 3 which causes certain problem with specific operating systems. Ena- bling "Max CPUID Value Limit" will limit the returned value to 3 and less to get rid of the problem. The problem is not seen with Windows series operating sys- tems so the default is set to disabled for it.

Virtualization Technology (Only for the CPU with Dual Core) Virtualization Technology will allow a platform to run multiple operating sys- tems and applications in independent partitions. With virtualization, one compu- ter system can function as multiple “virtual” systems. With enhancements to Intel’s various platforms, Intel Virtualization Technology can improve the ro- bustness and performance of today’s software-only solutions .Settings: [Enabled], [Disabled].

Execute Disable Bit

Execute-Disable Bit capability is a robust hardware feature, detectable using the CPUID instruction, that protects against malicious software executing code on IA-32 systems.Settings: [Enabled], [Disabled].

Hardware Prefetcher

This item allows you to to enable/disable the hardware prefetcher, or in other words – hardware prefetch mechanism.Settings: [Enabled], [Disabled].

Adjacent Cache Line Prefetch

This item allows you to enable/disable the adjacent cache line prefetch mode. When disabled, only one 64 byte line from the 128 byte sector is prefetched (which contains the requested data). When enabled – both lines are prefetched no matter whether they have or have not the requested data. Setting options: [Enabled], [Disabled].

Hyper-Threading Technology

The processor uses Hyper-Threading technology to increase transaction rates and reduces end-user response times. The technology treats the two cores inside the processor as two logical processors that can execute instructions simultaneously. In this way, the system performance is highly improved. If you disable the function, the processor will use only one core to execute the instructions. Please disable this item if your operating system doesn’t sup- port HT Function, or unreliability and instability may occur.

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