Reader Abasse Asgaraly wants to know when it's O.K. to leave a computer on standby instead of shutting it down. He asks: After recent problems with my Dell Dimension CPU fan, which needed to be replaced, the tech guy told me to shut down my computer when I am not using it. I am putting it on standby mode instead because that makes it easier and quicker to start it again. Do you think the standby function saves as much power as a full shut-down? What would you recommend?
In a system running Windows XP, you actually have three choices: shut down, hibernate, and standby. Unless your computer is in need of rebooting, and all of them need a restart from time to time to clean out the junk that accumulates in Windows, you will want to go with either standby or hibernate. To manage these functions, go to the Control Panel and choose "Power Options," then click on the "Advanced" tab.
Standby (also called "suspend") drops the computer into a very low power mode. The display turns off (on a desktop, depending on the monitor type, you may have to turn off the power on the display to achieve maximum power savings), the disk drive stops spinning, and the processor shuts down almost completely. In standby, power is used mainly to keep the contents of random access memory refreshed.
A LONG NAP. Hibernate goes a step further. The current state of the computer is saved in a special file on the hard drive and the laptop shuts down completely, drawing no power. When you restart from hibernate, that file is reloaded and the computer is returned to exactly the condition it was in.
Both standby and hibernate allow you to go back to work exactly where you left off. The main difference is that the return from standby is almost instantaneous, while waking up from hibernation can take almost as long as booting up the laptop. (A laptop on battery power left in standby will eventually hibernate when the battery charge drops low enough.)
Unless you are shutting down for a long period of time, the choice of hibernate vs. standby is unlikely to have any significant effect on the life of your computer. On desktops, the fans are designed for continuous duty cycles, and many are thermostatically controlled. But hibernate will achieve the maximum power savings at some loss of convenience.