Sleep state
Sleep state is a low-power state supported by many modern x86
microprocessors. In this state the core maintains its context, its
internal clock is stopped and internal clock of L2 cache is running.
While in this state, the CPU may not respond to interrupts and other
signals. This state is always entered from
Stop Grant low-power state.
From this state the CPU may transition to even lower power state - Deep Sleep state.
Sleep state offers better power-savings than Auto Halt Power Down
or Stop Grant states, but it requires more time to return from this state
to normal operating mode.