the difference between Sleep, Standby, and Hibernate?
Standby puts your computer into energy-saving
mode, where it uses very little power.
your workspace (all your open windows), then turns the computer off.
The difference is that hibernate saves more
energy because the computer goes off completely, but it takes longer
for the computer to wake up from hibernation, so it's not as convenient.
Time to sleep/wake up
a few seconds
30 secs. to 3 minutes
Sleep is more
complicated, because it means different things on different computers.
Mac OS, desktop. Sleep is the same as Standby. There
is no built-in way to Hibernate.
Mac OS, laptop. Sleep initially means Standby, but
if the battery level drops very low then the laptop automatically
Hibernates. See below for more on this.
Windows Vista. Sleep initially means Standby, but it
switches to Hibernate if the battery level drops too low (laptop) or
the computer has been sleeping for more than three hours (both desktops
& laptops). You can change the 3-hour period to something else in Settings
> Power Options.
Windows XP. ???
Hibernate on Windows Vista
As mentioned above,
Hibernate happens automatically in Windows Vista for both laptops and
desktops after the computer has been sleeping for a while. Laptop users
can skip to the chase and just choose Hibernate manually. That option
isn't available to desktop users by default, but this article shows how to enable Hibernate for desktop computers.
It's also helpful if the Hibernate option has disappeared from your
laptop for some reason.
Hibernate on Mac OS ("Safe
Hibernation "Safe Sleep". That's what I'll call it too for the rest
of this article.
see fit to let the user choose Safe Sleep on their computers.
Sleep happens on laptops only if it's sleeping and the battery level
drops too low, and even then only on PowerBooks made after October
2005. You can override that behavior and get your Mac (laptop or
desktop) to Safe
Sleep immediately on demand with software like Deep Sleep, SmartSleep,
or SuspendNow (or see the hacks at Mac Simple Life or MacWorld).
(Trivia: Apple used
to let users choose Safe Sleep. On the old clamshell iBooks, circa
2000-01, running Mac OS 9, there was an option called "Preserve memory
contents on sleep".)
Which should you
use: Standby, Hibernate, or Shut Down?
You probably want
Standby, because it's the most convenient.
With Standby it takes only a few seconds for your computer to wake
up. With Hibernate or Shut Down, you have to wait 30 seconds to 3
minutes for it to start up again.
Hibernate or Shut
Down will save more energy, but not much.
Six watts x 23 hours a day x 30 days a month is 4.1 kWh, which at
15¢/kWh would cost you 62¢/mo. If that kind of savings is
important to you, then sure, hibernate or shut down your
computer. Otherwise, just set your computer to standby so that it
wakes up quickly the next time you want to use it, and don't worry
about the very small difference in energy use.