The following table lists the system power requirements when using several popular graphics cards. These results were obtained with a different motherboard than the one listed in our test setup, but the difference is clearly in the single-digit range and thus negligible. 2D reflects the power draw under Windows, while 3D represents the power requirements when running 3DMark06.

Check list:

• If you want to save energy, select a graphics card that offers both adequate performance and acceptable idle (2D) power requirements.
• Do not use a discrete graphics cards in favor of a platform with integrated graphics if you want to minimize power requirements and heat dissipation.

Savings: The idle power requirements differ tremendously whether you run integrated graphics or a powerful discrete graphics card. Simple graphics cards consume as little as 25 W while high-end models require at least 40 W, whether they are active or not.

Display

When we talk about system power requirements of 60 to several hundred Watts, this number never includes the display! We already mentioned it: Turn everything off that you don't need. CRT monitors at 19" and up require at least 100 W; TFT displays start at 25 W and may go up all the way to 50 W, depending on the screen size. Power users tend to use two displays, while some people like our Webmasters even use three, which effectively can make your displays the real power eaters in the system. All displays are capable of going into a power saving mode, which reduces the power requirements to only a few Watts.

Check List:

• Use power saving options to put displays in standby mode when they're not needed (especially if you have more than one display).
• Switch off displays when you leave for the night.
• Use smaller displays instead of multiple smaller displays.

Savings: This largely depends on the type of display. Since the display(s) typically are responsible for 20-30% of the system power draw, switching them off when they're not needed saves considerable energy.

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