Guest post by No, not the kind of power you’re probably thinking of. A recent independent test ranked Red Hat Enterprise Linux 5’s power efficiency over Novell’s SUSE Linux Enterprise and Microsoft Windows Server 2008 on three different hardware platforms. RHEL averaged about 10% more power-efficient than Windows Server 2008 on the same hardware.
Some recommendations for the desktops:
On CRT monitor (if those still exist), you can save a lot of energy with a dark background. Plain black is the best. You can also set your browser settings to display text white on black. It does a very big difference. I measured 45 Watts with a colored background, and 24 watts with a black background (almost tha half).
Also, do not activate window manager compositing, it consumes a lot of energy (this can almost double your energy consumption. For NVidia cards, the nv driver is more energy efficient than the nvidia one, maybe because it doesn’t use all the advanced features of the card. You can have both drivers for different layouts activated in your xorg.conf config file and switch layout when you need the extra functions.
Do not activate the GL screen savers. They consume more energy than when the computer is idle. It’s better not to have any screen saver at all. Switch off the monitor instead.
WIFI consumes a lot of energy. If you are just next to your router, put a wire and switch the WIFI off. You gain in both performance and energy consumption. Most routers allow to switch WIFI off in their configuration. When not used, you should switch the router off as well (some routers consume more than a fridge!). Worst is surfing the web with 3G usb key.
Choose your components wisely. If you just browse the web and send emails, don’t buy a quadcore supercomputer. Choose the low power ones.