Search results
Results From The WOW.Com Content Network
The CPU power states C0–C3 are defined as follows: C0 is the operating state. C1 (often known as Halt) is a state where the processor is not executing instructions, but can return to an executing state essentially instantaneously. All ACPI-conformant processors must support this power state.
Advanced power management (APM) is a technical standard for power management developed by Intel and Microsoft and released in 1992 [1] which enables an operating system running an IBM-compatible personal computer to work with the BIOS (part of the computer's firmware) to achieve power management.
The power management for microprocessors can be done over the whole processor, or in specific components, such as cache memory and main memory. With dynamic voltage scaling and dynamic frequency scaling , the CPU core voltage , clock rate , or both, can be altered to decrease power consumption at the price of potentially lower performance.
SCI from the Embedded Controller to inform the ACPI driver (in the OS) of an ACPI Event; As a core system component, the embedded controller is always on when power is supplied to the mainboard. To communicate with the main computer system, several forms of communication can be used, including ACPI, SMBus, or shared memory.
Local APICs (LAPICs) manage all external interrupts for some specific processor in an SMP system. In addition, they are able to accept and generate inter-processor interrupts (IPIs) between LAPICs. A single LAPIC may support up to 224 usable interrupt vectors from an I/O APIC. Vector numbers 0 to 31, out of 0 to 255, are reserved for exception ...
ACPI 1.0 (1996) defines a way for a CPU to go to idle "C states", but defines no frequency-scaling system. ACPI 2.0 (2000) introduces a system of P states (power-performance states) that a processor can use to communicate its possible frequency–power settings to the OS. The operating system then sets the speed as needed by switching between ...
It is derived from I²C for communication with low-bandwidth devices on a motherboard, especially power related chips such as a laptop's rechargeable battery subsystem (see Smart Battery System and ACPI). [1] Other devices might include external master hosts, temperature sensor, fan or voltage sensors, lid switches, clock generator, and RGB ...
The MultiProcessor Specification (MPS) for the x86 architecture is an open standard describing enhancements to both operating systems and firmware, which will allow them to work with x86-compatible processors in a multi-processor configuration. MPS covers Advanced Programmable Interrupt Controller (APIC) architectures.