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For many years now, I've been shutting off my computer at night. But I'm now convinced you can leave your computer on at night and still conserve as much energy.Is 7.3 watts zero watts? No. Do computers or monitors use zero watts when they are switched off using their on/of switches? No. Is five watts "a few microwatts"? No.If you're a Windows user (Windows XP, Windows 2000, Windows Me), just set up your PC to 'hibernate' overnight. 'Hibernate' powers down your monitor to about 5 watts of energy and your PC to 2.3 watts -- virtually the same as turning your PC off...
Screen savers do not reduce your power consumption, and they are rarely necessary to protect modern monitors from image burn in. They aren't really "screen savers" anymore, they just look pretty and conceal your underlying display from snoopers.
Actually, the only reason it even draws that minute amount of current is because that's what it draws when it is "off" (and the amount of course will vary from one make/model to the next). Frankly, if anything those figures seem high to me for actual hibernation mode.
'Hibernate' powers down your monitor to about 5 watts of energy and your PC to 2.3 watts -- virtually the same as turning your PC off...
Once you put your computer into "Hibernate" mode, you CAN unplug it -- and it will still come back to the exact desktop state you were in when you hibernated (i.e., your applications will be loaded, documents open, windows exactly were you left them, etc.)
Now, there is a sort of "intermediate" mode between fully powered-up and shut down via "hibernate" mode. This is called "Standby" mode. The computer is still running, but, at greatly reduced power (making the figures above seem more realistic). The CPU is slowed down to a snail's pace (just enough horsepower to know if "something happens", such as a keystroke or other "wake-up NOW!" signal), the hard drives are spun down, and so forth.
For "standby" mode, you do need to keep the power plugged in -- and, the system will "wake up" nearly instantly when you strike a key (or whatever). When you put it into hibernation, though, it has to go through the boot process, but, it goes pretty quickly, since once it gets past the bootstrap loader, all it needs to do is "undump" the previous RAM contents off the disk and back into memory (and, a tiny bit of "housekeeping").
I regularly "hibernate" because we have frequent lightning storms, and I'm sick and tired of replacing hardware. So, I hibernate, pull the plugs, and go read a book. When the storms pass, I reverse the process, and I'm right back where I started.