By Scott Dunn Computers and computer peripherals consume dramatic amounts of electricity every year, draining your budget and contributing to greenhouse gases. But for little or no money, you can reduce the number of watts your system and peripherals use, saving cash and limiting the environmental damage.

What’s the easiest way to go green?

Too often, grand concepts like “green computing” are like the weather: everyone talks about it, but nobody does anything. Like it or not, the construction and use of computers still involves hazardous materials and the production of greenhouse gases. Is there anything you can do now without waiting for the perfectly constructed, solar-powered, recyclable computer? Fortunately, the answer is yes.



Without spending any money at all, you can reduce your power usage (saving on climate-changing CO2) and lower your electrical bill at the same time. And, if you’re willing to spend a little on a couple of useful gadgets, you may be able to save even more. Here are a handful of ways to save money while you save the earth.

To sleep, perchance to save

Many of us think nothing of leaving our computers powered up while we go to lunch or even 24 hours a day. A study in PC World found that a running computer consumes between 195 and 305 watts, while a computer in suspend mode can consume as little as 10 watts. Hibernation mode consumes slightly less at 9 watts of power (assuming the PC remains plugged into the wall socker), but hibernation takes longer than suspend mode to wake up from.

You probably already know that Windows provides options for both modes via the Power Options control panel. But Windows consults your BIOS to decide exactly what to do in suspend mode. Most modern BIOSes follow the Advanced Configuration & Power Interface (ACPI), an open power-management standard that was developed by HP, Intel, Microsoft, Phoenix, and Toshiba. (You can download a PDF version of the ACPI spec from the ACPI.info Web site.)

Depending on your particular BIOS, you may be able to choose from any of the following states:

S1. In this state, the CPU stops processing but remains powered. RAM is also powered, but some devices may be powered down.

S2. This option, omitted from many BIOSes, is like S1 but also shuts down power to the CPU.

S3. This state leaves RAM powered, but not much else. This “suspend-to-RAM” feature is what lets you resume where you left off, since your computer’s state is still in memory.

S4. This state powers down RAM, requiring your data to be written to the hard disk if it is to be preserved. It provides only marginal power savings over S3, but is the safest mode for your data if power is cut off entirely. This scheme corresponds to Windows hibernation mode, and is seldom found as a BIOS suspend option.

Get the best from your BIOS

To make sure you’re getting the greatest power savings from Windows’ suspend feature, follow the steps below. Specifics are not possible for all steps, since setup screens vary from one BIOS to the next.

Step 1. Save all open documents and restart your computer.

Step 2. Follow whatever prompts you see on your screen to enter Setup. Usually this involves pressing Delete or a function key.

Step 3. In Setup, locate the page or screen associated with power settings. It may be labeled something like Power or Power Management Setup.

Step 4. When you find the proper screen, highlight the setting related to suspend mode. It may have a label like ACPI Standby State or Suspend Mode.

Step 5. Change this setting to S3. The option may be labeled “S3 only” or “S3/STR” (for Suspend To RAM).

Step 6. Follow the instructions on screen for saving your settings and restarting your computer.

Work it with Windows

Now make sure Windows is using suspend mode when you’re not working.

Follow these steps for Windows XP:

Step 1. Open the Power Options control panel.

Step 2. On the Power Schemes tab, click the System Standby drop-down list under Plugged in. Select how long your system should be idle before starting suspend mode — for example, After 30 mins. Click OK.

Follow these steps for Windows Vista:

Step 1. Open the Power Options control panel.

Step 2. In the task list on the left, click Change when the computer sleeps.

Step 3. Click the Put the computer to sleep drop-down list under Plugged In. Choose the period of inactivity after which suspend mode should start — for example, 30 minutes. Click Save changes.

Give suspend a nudge

Windows sometimes interprets background tasks (like network activity) incorrectly and remains awake when it should go into suspend mode.

If you have that problem, a simple program called CO2 Saver may help. Once installed, it sits on your desktop and shows how much CO2 you (and other users) have saved by using suspend mode.


Figure 1. Snap CO2 Saver puts Windows into sleep mode even when the operating system wrongly believes there is activity.

To make CO2 Saver encourage Windows’ suspend mode, click the Options link at the right end of CO2 Saver. (If you don’t see the Options link, click the right-arrow to expand the toolbar.) With the Power Saving tab in front, choose Custom from the drop-down list. Then click the link below. In the Custom Power Saving dialog box, check Initiate sleep mode if system doesn’t sleep automatically. Click OK twice.

Make it manual

You can also put your system into suspend mode manually any time you want:

In XP, choose Start and then click Turn off Computer. Click the Stand By option.

In Vista, choose Start, click the arrow button in the menu’s bottom-right corner, and choose Sleep.

In Vista, sleep mode may be the default, so simply clicking the power button in the Start menu puts the computer to sleep.

Try other low-power moves

In addition to getting the most out of suspend mode, you can take other steps to reduce your power consumption and save money:

Use a power strip. Plug peripherals (like printers, audio systems, monitors) into a power strip or UPS. Then turn it off when you want all of your equipment to turn off.

Lose the brick. Once your laptop or notebook computer is fully charged, unplugging the recharger from the wall will save some electricity. As long as the computer is in suspend mode or some other low- or no-power mode, it won’t need to be plugged in again for hours.

Lose the CRT. According to Sask Power, LCD monitors use 66% less electricity than the older CRT type. Maybe this is the time to switch to that LCD screen you’ve been wanting. If you can’t afford to change right now, at least get in the habit of turning off the CRT’s power switch every time you leave your desk for more than a few minutes.

Check power saving options. See if your printer or external hard drives have power-saving modes. For example, many of Western Digital’s external “My Book” hard drives have a GreenPower feature.

Use a smart power strip. Some newer power strips use a motion sensor to decide if you’re still at your computer. If not, they shut down power to certain sockets (such as ones for peripherals) after a user-designated time has elapsed. Other power strips shut off several sockets, based on whether you’ve powered down a device plugged into the “control” socket. The Tree Hugger Web site discusses examples of each.

You don’t need to wait for new computer designs to make your computing a little more green friendly. By tweaking a few settings and getting into a few good habits, you can make a difference for your pocketbook and the planet.

Have a tip about Windows? Readers receive a gift certificate for a book, CD, or DVD of their choice for sending tips we print. Send us your tips via the Windows Secrets contact page.

Scott Dunn is associate editor of the Windows Secrets Newsletter. He has been a contributing editor of PC World since 1992 and currently writes for the magazine’s Here’s How section.

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