What is "System standby," exactly?
 

I am all for saving as much energy as I can but I don't want to inconvenience myself too much to do it. So, to this end, I am looking for a deeper understanding of some of the power features of Windows, "System standby" in particular.

I can imagine, generally, what it does. It powers the system down into some kind of power saving mode since you're not really using it. However, I wonder how this works, exactly. Are your computer components still on? What powers them back on? Will it only power back on from recieving user input or can it power itself back on due to other stimuli, such as network activity or a scheduled process? It would be a shame to have scheduled tasks fail to run, or downloads fail to complete, simply because your computer was in or went into "System standby" mode...

I assume "System hibernates" mode actually turns off your computer so it really is doing nothing and will not stay that way until you physically turn it on...

I do not know much about system standby, but I do know what Hibernate is.

When you restart your computer, your computer refreshes the memory, i.e. your programs that were running are gone. However, when you "hibernate" your computer, it goes through the same process as shutting down except it does not clear your memory, so when you restart, it will be the same as before.

Hibernate dumps the physical memory to the hard drive in the hybersys.sys file (or something close to that in the system drive root directory) standby is the older version of hibernate it is clunky (both are) but hibernate works most of the time. With standby the system must remain on but it uses very little power, with hibernate it can be shut completely off.

Thanks for the clarification Dilbert.

Yes, and hibernation's very handy if you don't want to shut everything only to open them again when you start up.

I usually use hibernation on my laptop when I know that I will be reconnecting soon. Standby was a mess. The system would come back, but it usually required a reboot to get anything valuable working again.

I think I remember reading that standby turns non-critical devices (video card, sound card, network card, usb, etc) off and keeps low power to your RAM so that it doesn't loose what is stored in it at the time. Thats why if you put your laptop on standby and leave it, the battery will eventually run out and you will have to cold boot whereas hibernation, as Dilbert said, dumps out to a file on the hard drive and is read back in when you turn your computer back on.

If you check out your system devices in Device Manager you should see a power management tab when you check the properties of your network card. That'll give you options about turning off devices when not in use and also one for allowing devices to bring it out of standby etc.