Jeff said:
What's the difference between sleep and hibernate? Does the computer
come on when you move the mouse or touch a key with both of them. When
running Superantispyware it give me choices: when it's done to shutdown
sleep or hibernate which should I choose if I'll be using it right away
and don't want to have to go through a startup
Jeff
Sleep and hibernate, are states where the CPU is not running.
Their intention is to save power, while you're not using
the computer. And at the same time, to preserve the system
state (open programs) for you.
Sleep stores the session in RAM. This is a form of volatile storage.
If the AC power were to go off, the computer eventually runs out
of +5VSB to power the RAM. All your work (open files not saved) would be
lost.
Hibernate, stored the contents of RAM onto the hard drive, in hiberfil.sys
file. When a computer is restarted, after being in hibernation state,
the disk contents are read and put back into RAM. Then, the program
counter is loaded with the last used address, and the computer
picks up where it left off.
Hybrid sleep is available on some later OSes. It stored the session in
both RAM and disk. If the computer is not powered off, the RAM stuff
can be used directly. If the computer is powered off, the contents of
the hiberfil.sys are there.
*******
"Wake-up" is a separate issue.
Pressing the power button on the front of the computer, is
likely to always work. The power button is biased by +5VSB,
and if the ATX supply is getting any power at all inside,
it makes that voltage. The power button is not likely to be
gated off.
Wake on mouse or Wake on keyboard, require two things.
They need electrical power. Modern motherboards always
run the keyboard and mouse from +5VSB. On some keyboards
(like mine), I see a glowing LED which tells me when the
computer is off, the keyboard has power.
The second necessary step, is a visit to Device Manager.
Do "Properties" on the mouse and keyboard entries. There
should be a tab in properties, where it says "Allow this
device to bring the computer out of Standby". That should
be ticked.
In the BIOS, there is an entire page dedicated to power
related things. And wake functions (with the abbreviation
PME or Power Management Event) can be found there. If
the Device Manager entry was grayed out, you could
check the BIOS to see if something there is the issue.
PCI cards have an actual PME signal available to them. THat's
how a NIC (network) card is able to wake up the computer,
if a Wake On LAN packet is received. The chipset also has
PME, and the mouse and keyboard may eventually find their
way to driving such a signal. So a number of things have
waking capabilities. And other things do not - your hard
drive cannot wake the computer, if the hard drive is
having a bad day. It's the keyboard, mouse, touchpad,
NIC, Wifi (for the ones that are "Always On) and so on.
*******
You want "Sleep" for the situation you describe.
The Power Button is most likely guarantee to wake
it up. Whereas other HID devices, may need Device
Manager adjustments.
And you test Sleep, with the computer booted, and not
doing anything important. Make sure Sleep is working
properly, before trusting open files to it, so you
don't lose any work.
Occasionally, a computer with bad RAM, cannot sleep
properly. Or, it can be the chipset which does not
transition well, from fully powered, to sleep powered
state. For those computers, simply use hibernate,
as it's a more rock solid option. I think I've had
at least one computer here, which doesn't sleep properly.
So that one just hibernates if I want to take a break.
HTH,
Paul