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Each box comes with only the components needed for each application. As such, the
overall cost is less than buying a server out of the Dell catalog. On top of that savings,
Ask.com has cut server power usage by 30 percent.

NOTE Ask.com isn’t the only company getting its servers custom made. Dell launched a program in
2007 in which it will customize servers for its largest customers—those who buy at least 1000
servers each quarter.
Computer Settings
Although establishing policies to govern your computers’ monitor power settings is a great
place to start (and we’ll talk about that more in a moment), there are some other places
where you can make more precise changes for real savings.

Polling
Periodic polling—that is, the computer automatically checking to see if a given action has
been taken—draws power from idling computers, because it automatically wakes the
computer up to check for a given event.
Every time an application polls for something, the CPU wakes from an idle state and
consumes power.
You might not be able to eliminate all your polling tasks, but you can manage them.
Let’s say you have 10 polling actions that occur within 1 second. Schedule them so that they
run immediately after another, rather than at various times during that period. Figure 3-5
demonstrates this.

NOTE If a computer is in an idle state, allow it to remain idle as much as possible. The more the
computer wakes up (for polling or from someone moving the mouse), the more energy it will
consume.

By grouping them together as the figure shows, the computer only has to come out of an
idle state once, rather than multiple times.
Turn Off Unused Devices
This seems like a no-brainer. If a computer or other device is not going to be used in the
foreseeable future, turn it off. Failing that, at least set up the computer so that it hibernates
after a certain period of nonuse.

FIGURE 3-5 One second
Group your timers
together so that
they reduce the
amount of time the
computer has to Timers spread out
be polled.
Timers running back-to-back