IT Chapter 2 Part B
CPU
CPU
• The CPU is contained on a single integrated circuit
called the microprocessor.
• Often referred to as the brains of a computer
• The CPU contains two basic components:
– Control unit – Instructs the rest of the computer
system on how to follow a program's instructions.
It directs the movement of data to and from
processor memory
– Arithmetic/Logic Unit (ALU) – The ALU performs
both arithmetic and logical operations
• The processor handles most of the operations that
are required of the computer by processing
instructions and sending signals out, checking for
connectivity, and ensuring that operations and
hardware are functioning properly
CPU cont.
• The microprocessor is connected to the rest of the
computer system through three buses, including the
data bus, address bus, and control bus
• Many different companies that produce CPUs,
including Intel, Advanced Micro-Devices (AMD)TM,
and Cyrix
• Socket X (X being any numerical number) is a
descriptive term for the way certain processors plug
into a computer motherboard so that it makes contact
with the motherboard's built-in circuitry or data bus
• Zero Insertion Force (ZIF) socket. A ZIF socket is
designed to make it easy to replace and upgrade the
microprocessor. A typical ZIF socket contains a lever
that opens and closes, securing the microprocessor
in place
Pentium Processors
• Current family of the Intel Pentium
microprocessors includes the Pentium II, III,
IV, and Pentium D’s , Dual Core
• Pentium class is the current standard for
processor chips
• The combined chips cover less than 2 square
inches (6 cm2) and comprise over a million
transistors
AMD Processors
• Advanced Micro Devices (AMD) processors
are the Athlon, Thunderbird, Duron series, A
Series, FX Processors, Phenom II and APU’s
• AMD is first to break the historic 1GHz (one
billion clock cycles per second) with the AMD
Athlon™ processor.
Processor Speed Rating
• CPU descriptions as Pentium 133, Pentium 166, or
Pentium 200 are well known
• These numbers are specifications that indicate the
maximum (reliable) operating speed at which the
CPU can execute instructions.
• The CPU speed is not controlled by the
microprocessor itself, but by an external clock located
on the motherboard
• It is typically expressed in megahertz (MHz), and the
higher the number, the faster the processor
• Generally, three factors determine how much
information can be processed at any given time.
These include:
– The size of the internal bus
– The size of the address bus
– The processor's speed ratings