Datasheet

CPU
The central processing unit (CPU), or microprocessor, is the brain, or at least the
manager, of all the data and instructions that pass back and forth within the
machine. Most modern laptops use a modified version of the same microproces-
sor employed by desktop computers; designers have come up with many ways
to reduce the amount of power that processors demand, which helps extend
battery life and also reduces heat buildup (which also cuts down on power use
by the fan).
Some of the most current microprocessors, including the Intel Centrino M, can
adjust their speed and power use depending on the task they’re performing. The
Centrino technology includes a CPU, a supporting chipset, and a wireless trans-
ceiver. The chip itself is the Pentium M. If the computer includes all three parts,
the manufacturer can call it a Centrino system; if it lacks the WiFi circuitry, then
the laptop is called a Pentium M system.
Other Intel chips used in laptops include mobile versions of the Core 2 Duo
processors, sometimes identified as Mobile Core 2 Duo, and the slightly less
capable Core Duo processors.
Advanced Micro Devices, the only significant Intel competition in the laptop CPU
marketplace, has its own series of highly capable microprocessors. Current
chips include the Mobile AMD Sempron and the AMD Turion 64 X2 Dual-Core
Mobile Technology.
Memory (also known as RAM)
Memory is the place where the computer gets its work done. This is the scratch-
pad, the assembly place for your words, numbers, pictures, and sounds before
you manipulate, display, print, or file them away in storage for future reference.
Memory is more properly referred to as
random access memory (RAM), because
the computer can reach directly into the chip to find a piece of information with-
out having to go through everything else in front of it.
Another important thing to remember about RAM is that it’s
volatile, or tempo-
rary; it requires a near-continuous source of electrical power and regular
refreshing of its contents. Let me put it another way: Turn off the laptop and
RAM loses its memory.
And finally, more memory is generally better than less memory. Your processor
works faster if it can work on data in RAM instead of having to retrieve it from
storage (a hard disk, for example). The downside to more memory in a laptop is
that the chips require power and also generate more heat, which fans must
remove. Therefore, a battery’s working time in a system with a lot of RAM is
shorter than in a system with less memory.
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