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这里说我用的CPU只支持C1 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. Some processors, such as the Pentium 4, also support an Enhanced C1 state (C1E or Enhanced Halt State) for lower power consumption,[7] all processors must support this power state.

CoolCore只是clock gating? here AMD CoolCore™ technology is part of logic design within our processors and chipsets. Because this technology is part of the silicon design, no drivers are required to garner the benefits in power reduction. This technology is enabled through what is called “clock gating”. If certain portions of logic, enabled with clock-gating, are not being used for a given operation, those logic clocks are turned off. For example: if the memory controller is doing a lot of reads, then the write logic of the memory controller can be clocked off. This is like shutting off the lights in an unoccupied room in the house since the room isn’t being used.