Does Windows use an RTC wake up to switch from suspend to hibernate?

Question

In Windows 7 power management, you can state that suspend should happen after x minutes, and hibernate should happen after y minutes.

So if x=10 and y=180, then the machine must come out of suspend at 180 minutes in order to carry out a hibernate.

If we want to do a similar thing under linux, we use RTC wake to tell the bios to automatically unsuspend in time for the hibernate process to happen (see this)

My question is - are these approaches the same, is Windows doing the same thing? Or does Windows do something else to get from one state to the other?

(note that this is not hybrid sleep, which allows for power-loss during suspend by effectively doing a hibernate before suspend - the above process works even with hybrid sleep disabled)

Answer 1

Windows 7 uses the Task Scheduler to accomplish this. In order to wake the computer, Windows uses the "BIOS timer from sleep or hibernation to execute a scheduled task or run a previously scheduled task after a machine gets turned on." Wikipedia Reference

This should be very similar to the method that Linux uses. Both rely the BIOS to wake the computer after a set period of time.