CPU and the Chip Set
o Some of the most popular types of processors are made by Pentium, AMD
o How the CPU Works?
The CPU contains three basic components:
I/O unit – manages instructions that come to and leave the
One or more arithmetic logic units (ALU) – completes all
comparisons and calculations.
Control unit – manages all activities that take place in the
Data and instructions are stored in places called Registers.
Registers hold data, counters, instructions, and addresses
that the ALU is currently processing.
The CPU also has internal cache memory that holds data and
The CPU has its own internal bus for communication with
the internal cache.
The internal bus operates much faster than the external,
These buses are also called back-side bus (BSB) and the
front-side bus (FSB)
o How to Rate CPU’s
Processor core speed measured in gigahertz: An average CPU
speed today is about 3.5 mega hertz.
Word size: sometimes called the internal data path size, is the
largest number of bits the CPU can process in one operation.
Data path: sometimes called the external data path size or (FSB) is
the largest number of bits that the CPU can transport at a time.
Efficiency and special functionality or programming code:
programs that accomplish fundamental operations, such as
comparing or adding two numbers.
The system bus speeds the processor supports: typically run at 400
The type of RAM, motherboard, and chip set the processor
supports: the processor must fit the motherboard and the chipset
embedded in it, and the motherboard determines what type of
RAM you can use.
Multiprocessing ability: some microchips are really two processors
in one and can do more than one operation at a time.