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Intel Processor Power Management

Modern Intel processor power management is based on a combination of two techniques: changing the CPU frequency (P-states) and using idling power states (C-states). A third technique, used on older processors but rarely on modern processors, is throttling of the CPU (T-states). P-states are voltage-frequency pairs that set the speed and power consumption of an Intel processor. When the operating voltage of the processor is lower, so is the power consumption. C-states are idle power saving states, in contrast to P-states, which are execution power saving states. During a P-state, the processor is still executing instructions, whereas during a C-state