Hibernate basically copies the actice RAM to the HDD and shuts down, saving the system state. So HIBERNAT.SYS will be equal to the amount of physical RAM you have in the computer.
And for clarification, the Hibernation shuts the PC completly down, standby olny puts it into a reduced power state. Modern computers will still have all the fans and stuff running whe in standby mode, therefore not conserving much power anyway. Hibernation reduces power usage to 0 and shuts the machine completly off, but allowing you to restore your session to where you left it
allan - dummy question - Did I not read somewhere to set the monitor to turn off before the hard drive?
If so - does it really matter - or can I just set them both for say 20 minutes??
Also how does this affect the screen saver? - If screen saver turns on after 10 minutes and monitor turns off after say 20 minutes - I end up with sound from the screen saver and no monitor. What if I turn off the hdd after say 25 minutes - no nothing?
Hey damnyank - I have my display powering down after 25 mins and the hd after 30, but it's really no big deal one way or the other.
As for screen savers, if I remember correctly I believe 3D screensavers will overide power down options while standard 2D screensavers will not - but I'm not 100% certain of that. But I'm not a big fan of screensavers either. They also keep the system active for absolutely no reason (I know, they're pretty).
In the old days you needed screensavers to prevent burn-in. But with today's displays that's no longer a concern.
Thanx allan - I know, I know - but I have this really nice Princess Di screensaver and with the wife being from England - she likes to watch it - in return I get to play all day on the puter - sounds like a good trade off to me!!
 Just an after thought - do you suppose a screen saver would prevent an automatic restore point form being made - since the system has to be "idle" for a certain period of time to do the auto restore point??? I'll have to play with it in the near futrue and let you know. 
The problem may be that your nice Princess Di screensaver needs to access the HDD every once in a while. In that case, your HDD will never go to standby. It doesn't matter if you have your monitor standby before your HDD does or vice-versa.