Hibernation in Vista is the same as it is in Windows XP. Hybrid sleep is
actually a variation of sleep, not hibernation. Hybrid sleep combines
hibernation and sleep. For example, if my notebook is plugged in, sleep
simply enters the low power state in which memory is retained. If my
notebook is not plugged in, sleep puts the computer into hybrid sleep if
this is enabled in the sleep section of the advanced settings in power
options- the contents of memory are written to disk as they would be in
hibernation and then the computer enters standard sleep mode. If for any
reason the computer actually shuts down during hybrid sleep - that is, no
power to retain the memory, the state of running programs will be restored
to memory from disk , as would happen when the computer comes out of
hibernation. Be aware that hibernation and hybrid sleep may not be available
after running Disk Cleanup - see
http://support.microsoft.com/kb/928897.
Tyro
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