A PSS support PC is a computer system that implements and utilizes the PSS (Performance Support States) mechanism, which plays a crucial role in defining and managing its power states.
PSS defines the Power States available on a PC. These power states represent different levels of system activity and corresponding power consumption. By transitioning between these states, the PC can optimize power usage based on the current workload, leading to energy savings and potentially reduced heat generation.
For a PC to fully leverage PSS, it needs corresponding support within its operating system (O/S) and system firmware (like UEFI).
Here’s how the components mentioned in the reference relate to PSS support:
- PSS: As mentioned, PSS defines the Power States. It lays out the different levels of performance and power consumption that the system can enter.
- PCT (Performance Control): PCT is what allows the O/S to control Power State. The operating system uses this interface to dynamically request transitions between the defined PSS power states based on system load and user settings.
- PPC (Performance Present Capabilities): This is a configurable value, typically found in the system's firmware settings (like UEFI). In the UEFI the PPC is configurable and the higher the value you set it to, the more levels of Power States are available for the O/S to dynamically change between. A higher PPC value indicates that the hardware is capable of supporting a finer granularity of power states defined by PSS, giving the O/S more options for optimizing performance and power.
Essentially, a PC with PSS support means it has the necessary hardware and firmware capabilities to define power states (via PSS) and allows the operating system to manage these states (via PCT), often with the number of usable states being configurable (via PPC in UEFI). This enables the PC to operate more efficiently by adjusting its power and performance dynamically.
