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I have Hybrid sleep active which makes it so the computer sleeps and remains powered on in a low-power state while also creating a hibernation backup file.

If I leave my machine in this state and the power is cut, will the machine automatically resume when the power is restored or will I have to press power?

ie: does it remember that it was in sleep mode when power is supplied again?

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As long as the battery is good, it will remember. But, I don't think this is a real question. – Xavierjazz Feb 4 '13 at 16:58
Of course it's a real question and there is no battery, its a PC. – Enigma Feb 4 '13 at 16:59
@Enigma - All motherboards have a battery on them to retain the CMOS settings. – Shinrai Feb 4 '13 at 17:01
The CMOS battery supplies a negligible amount of power. Certainly not enough for a PC or even a NIC to run on but given the answer, I can see what he was referring to now. – Enigma Feb 4 '13 at 17:16
up vote 7 down vote accepted

It depends on what the BIOS is set to do.

Depending on your computer, the BIOS may have a power setting called something like

Return to power status.

Its normally under the power settings in the BIOS.

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Correct - this is completely up to the BIOS settings. (In my experience, most desktop boards default to "stay off when power resumes" and most server boards default to "return to last power state when power resumes") – Shinrai Feb 4 '13 at 17:00
thanks @Shinrai, couldn't remember the exact wording. – Steve Feb 4 '13 at 17:02
The exact wording varies based on the board as well, so no worries there - I was speaking broadly. :) – Shinrai Feb 4 '13 at 17:03
Thanks. My machine was set to restore last power state already but good to confirm. – Enigma Feb 4 '13 at 17:17

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