AMD PowerNOW Configuration (X8400, X8420, X8440)

This topic provides information about a feature available on the Sun Blade X8400, X8420, and X8440 Server Modules. Enabling the AMD PowerNOW Configuration feature allows the blade to go into a power saving mode that reduces CPU frequency and voltage during idle states, conserving power.

The AMD PowerNOW feature allows CPU P-State transitions to take place while operating system function occurs. In order to support this feature, the BIOS must detect the type of processor installed, along with its matching P-state table, during boot up. This configuration option is only available on blades equipped with AMD Microprocessors.

The P-state tables contain mappings of Processor P-States to Voltage Identifiers (VIDs) and Frequency Identifiers (FIDs). When a P-state table matching the installed processor(s) is found, the BIOS relays the P-state table to the operating system through the declaration of ACPI ASL objects.