Question What's the meaning for HW_ALL, SW_ALL and SW-ANY under BIOS. Answer This(PSD, P-State Dependency) actually is defined in ACPI SPEC. It’s basically about how to coordinate the P-State transition of processors. Here are the descriptions: In SW_ANY mode, the OS Power Manager (OSPM) is responsible for coordinating the P-state among logical processors with dependencies (all Logical Processors in a package) and may initiate the transition on any of those Logical Processors in the domain. The expectation from the OSPM is that transitions initiated on any logical processor in a specific domain will force a transition on all logical processors in that domain. Thus the OSPM is only required to initiate a single transition per processor SW_ALL -- In SW_ALL mode, the OS Power Manager (OSPM) is responsible for coordinating the P-state among logical processors with dependencies (all logical processors logical processors in a physical package) and must initiate the transition on all of those Logical Processors. The expectation from the OSPM is that transitions must be initiated on every logical processor in a specific domain in order to force a transition on all logical processors in that domain. HW_ALL – In HW_ALL mode, the processor hardware is responsible for coordinating the P-state among logical processors with dependencies (all logical processors in a package). The OS is responsible for keeping the P-state requests up to date on all logical processors. HW_ALL mode is the most likely recommendation for all BIOS supporting the Haswell server processor. Was this FAQ helpful? YES      NO Enter Comments Below: Note: Your comments/feedback should be limited to this FAQ only. For technical support, please send an email to support@supermicro.com.  Enter your email address below if you'd like technical support staff to reply:  Please type the Captcha (no space) 8 N Y 4 FAQ Stats FAQ ID Related Category / Keyword Date Posted Code 29482 BIOS: - BIOS Setting 12/12/18     Print Answer