CPU Basics
The Central Processing Unit (CPU) is often described as the 'brain' of the
computer. Perhaps describing it as the 'engine' may be more
appropriate - it has no innate intelligence of its own, and more
powerful CPUs cannot do more complex work; they simply work faster.
It is the job of the CPU to perform mathematical and logical
calculations and also to decode instructions from programs running in
the computer's memory. The faster the CPU can do this work the
faster the computer operates. In fact, there are other computer
components that may limit the speed of the computer, but the CPU speed
is seen as a major indicator of computer performance.
The CPU is sometimes called the processor, central processor or
micro processor. It is rated by the number of bits that can be
processed in a single instruction and the number of instructions that
can be executed in one second. Current CPUs are rated at 32 bits
or 64 bits, and their clock speed could be anywhere between 1.5 GHz to
3.5 GHz.
One Gigahertz (GHz) is one billion cycles per second. A 32-bit
2 GHz CPU can process 2 billion instructions per second, each with a
maximum length of 32 bits. 32 bits in binary numbers is capable
of expressing the decimal number 4,294,967,295. Long story short
-- a 32-bit 2 GHz processor is amazingly powerful.
Intel and AMD
The two major CPU manufacturers are Intel and AMD. They have
been competing with each other for years and often leapfrog each other
in terms of technological advances. The current leader seems to
be AMD with its 64-bit Athlon processors, but the real world
differences between top-of-the-line processors from Intel and AMD are
usually very slight.
There are several factors that determine whether a particular CPU
can be used with a motherboard. The most important is the
physical layout. The motherboard has to be able to accept the pin
design of the processor. The pin design is often referred to as
'Socket x', such as Socket A, Socket 939, or Socket 478.
Motherboards are designed to accept a particular family of processors.
Another important factor to consider when choosing a CPU is the
speed. Motherboards have a maximum processing speed, so if you
are trying to fit an older motherboard with a newer CPU, you might have
problems.
Choosing a CPU
Deciding on which particular CPU to buy depends a lot on what you
need it for. Office applications like word processors and
spreadsheets do not require a lot of computing power. Games are
among the most taxing of computer applications - often requiring the
fastest and most powerful components available.
If you are an avid computer gamer set your sights on a CPU rated at
3 GHz or more. Prices start at about $200 for a 32-bit processor
all the way up to more than $1000 for the latest 64-bit processors.
If you have more modest computing needs, you can get by with a CPU
in the 2 GHz range. These are much more reasonable in
price. They start at about $70 for 32-bit processor and 64-bit
processors are available at about $150. Processors in this range
are suitable for just about any computer application including
graphics, video work and audio recording.
If you simply need a computer for word processing and using the
Internet, consider getting a CPU in the 1 GHz to 2 GHz range.
These are the real bargains. They can be had for less than $40
for a 32-bit 1 GHz processor and most processors in this range are less
than $100.
