Windows Vista and Windows Seven implement a new energy-saving technique: the core parking.
This technique puts in a state of deep energy saving, if supported by the CPU, the cores not currently needed for the processing in progress.
Because sending in a state of energy saving and waking up a core is a fairly slow process, the operating system must try to guess whether a given core will be needed in the near future or not.
Like all forecasts, it may be wrong.
howto:
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