Is Hybrid Sleep on Windows 7 the same
as on Windows Vista?
In a word, yes.
In Hybrid Sleep mode, the system saves any open documents and programs to memory and to your hard disk, and then puts your computer into a low-power state as in normal Sleep/Standby state.
An advantage of hybrid sleep is that if a power failure occurs, Windows can restore your work from your hard disk. If a power failure such as a power outage occurs when your work is saved only to memory (as in Sleep mode), all work is lost.
In Hyrid Sleep mode, if the computer suddenly loses power, users can still recover to the last working state as when the computer enters hybrid sleep mode, because all data in memory is saved in the hiberfil.sys hibernation file. In this case, the computer is acting exactly the same with hibernation mode to resume computer activity and yet still enjoy the benefit of fast return to full operation from Sleep mode.
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