Reduce your PC’s power consumption with a Power Regimen.

The only place you used to have to worry about your computer using too much power was in midflight at 35,000 feet. These days load shedding, blackouts, brownouts and the coming increase in electricity rates have brought these concerns back down on the agenda. Managing your computers appetite for energy can save you money, increase its life and prevent data loss.

The flow of electricity is measured in Watts. In your average computer, the hard drive will use between 5 and 25 watts, your CPU will use between 50 and 95 watts and your flat screen monitor between 40 and 60 watts. A well furbished computer running full ball will burn anything from 300 to 500 watts – and sometimes more.

Eskom charges you based on how many kilowatt-hours you use. My last known electricity bill was 32 cents per unit of electricity (kilowatt hour). If my computer uses 500 Watts at full ball, that’s almost 16 cents per hour.

Sound like nothing? If you’re like me and your PC is turned on for 40 hours a week, your electricity bill could range in the hundreds every year. If you keep your PC on for three years, the amount of power youre using could represent a sizable portion of your computer’s original price.

Most PCs now support either Advanced Power Management (APM) or the Advanced Configuration and Power Interface (ACPI). To check your PC, select Start, Settings, Control Panel, System, click the Device Manager tab, open the System devices listing, and look for entries with either 'APM' or 'ACPI' in the name. If you don't find either, power management may be disabled or not installed on your PC--and enabling it can be tricky.

APM, the older and less flexible standard, has five settings, ranging from full on to APM off (see Figure 1). Adjust the settings in either the CMOS setup program or Control Panel's Power Management utility. The settings can conflict, however, so you may have to experiment.

Open your system's CMOS setup program--typically by pressing Delete or F1 as the PC boots up--and go to the Power Management menu. If there's no menu specifically for power, look through the other menus; you're certain to find something. When you do, choose the option that enables APM.

If this causes problems, force your PC to use the earlier--and potentially more compatible--APM version 1. Go back to Device Manager and choose Advanced Power Management support under 'System devices.' Choose the Settings tab and then check Force APM 1.0 mode (see Figure 2).

If your PC is fairly recent, it may support the newer ACPI specification, which is part of the OnNow effort by Microsoft and others to make PCs easier to use and to let them boot up and shut down faster.

ACPI's Standby mode makes restarts easy, and it allows a PC to "wake up" automatically to process e-mail, modem calls, prescheduled tasks, and other external input. It improves on APM by letting you control the power consumption of individual components. At the very least, Control Panel's Power Management utility should offer power control over the hard disk and the monitor.

You'll conserve the most power by setting your monitor to power down. Some 19-inch monitors devour up to 150 watts. Powering down is much better than running a screen-saver program. You'll extend your monitor's life while suppressing its voracious appetite.

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