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So I was looking through the Windows 7 power options via Control Panel today, and I realized I had a couple of unresolved questions as to the nature of various choices. I was wondering if someone could give me a clear and concise explanation of the difference between the following four selections:

  1. Sleep Mode

  2. Hibernate Mode

  3. Standby Mode

  4. Turn off hard disks after...

For example, regarding option 4 - does this mean that after the elapsed time limit, the computer will go into standby, hibernate, sleep, or just turn off? Below is an image of the options (albeit on a Windows XP system, but I think the same concepts should apply):

enter image description here

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Can you please clarify what you mean by option four? Mabye posting a picture would help. – wizlog Oct 25 '12 at 2:30
I have posted a picture. – John Roberts Oct 25 '12 at 2:33
Are you sure that's from Win7 and not XP? – Karan Oct 25 '12 at 2:40
Great! Here, after minutes 15 of inactivity (not moving the mouse or pressing keys), the monitor would turn off (your hard disc would still be spinning). After 45 minutes of inactivity, your computer would enter standby, the low power state I (try) to explain in my answer. Your hard disc wouldn't turn off. – wizlog Oct 25 '12 at 2:42
@Karan I mentioned in the question that the screen grab is from XP. I don't currently have access to my Windows 7 machine, but one needs only to go to "Configure Advanced Settings", or something of that nature, to access the equivalent "Turn off hard disks" option in Win 7. – John Roberts Oct 25 '12 at 2:43
up vote 4 down vote accepted

I'll try my best to simpify this as best I can.

Sleep and standby mode keeps the computer on in a low power state, and allows you to quickly resume what you were doing. Hibernate shuts down or hibernates your computer and saves all your open windows, so when you log back in you can resume what you were doing.

Shutdown closes all programs, and powers off the computer. Nothing open is saved, and the computer needs to fully boot up (load your startup programs...) when you turn it back on.

On Windows Vista (probably also 7,8) sleep is the same as standby, until the battery gets very low, then it automatically hibernates.

Turn hard discs off after... is intended for desktops to store the information both in memory (like the sleep and standby modes) and also on the hard disc in case power failure occurred. Because laptops have a battery, power failure is pretty uncommon.

Microsoft posted some helpful information on sleep and hibernation here Sleep-and-hibernation-frequently-asked-questions.

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So regarding turning hard disks off, would the computer completely shut down? – John Roberts Oct 25 '12 at 2:34
@JohnRoberts: Turning hard disks off will simply spin the drive(s) down. Also take a look at this. – Karan Oct 25 '12 at 2:41
@JohnRoberts No I don't think so, not completely. – wizlog Oct 25 '12 at 2:43
It would be helpful to expand on the difference between standby and sleep, hibernate and shut down, and a better explanation of power down hard drive – soandos Oct 25 '12 at 2:55
Edited my answer. – wizlog Oct 25 '12 at 3:06

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