May 9, 2008
You'd be suprised how much power you can save by turning off a device. Especially something like the wifi card. Those things are always scanning the air for signals. But as for a standard network card, I don't think you'd save that much. Here's a test you could perform in an afternoon: recharge your laptop to capacity, disable all power saving features like screen and drive shutdown, screensavers, etc., then disconnect the power. Record the amount of time it takes for the unit to hit 10% and shut itself down. Now, recharge it again, only this time turn off the network card. Time it again, see how long it takes before you hit 10% again. That should give you some idea of how much power you'll save. (You can probably figure out the exact kwH if you take the output wattage from your power brick and divide it by the number of hours difference between on and off.) I've found the best way to save power is to disable wifi when I'm not online, turn down screen brightness, disable indexing (in vista), and set the power saving requirements to maximum (short wait time to turn off screen, hard drive, etc...). You can even invoke cpu throttling, if your unit supports it.