A+ Hardware Service Technician: System Architecture

Previous Page - Next Page

Characteristics of a CPU

Chip Speed

The processor contains millions of transistors. The CPU is measured by its clock speed in MHz. One Megahertz is one million cycles per second. The first IBM PC CPU, the Intel 8088, ran at 4.77 MHz. Today’s PCs exceed 2 GHz (2,000 MHz!)

Math Coprocessor

Contained within the chip is a math coprocessor which handles floating point calculations, like algebra and statistics. The math coprocessor is also referred to as the FPU (Floating Point Unit). Earlier Intel chips had an additional chip which handled the math functions, but the Pentium line has had the functions built-in.

Cache Memory

Most processors have an internal cache which stores frequently used data and instructions. Cache is broken up into two classifications, L1 which is internal cache and L2 which is the external cache.

Buses

Each processor has buses which work with it.

The external bus, also called the system bus, allows the processor to connect with other devices such as expansion cards and devices.

Buses consist of two parts: data bus and address bus. The data bus transfers the information and the address bus tells where the information should go.

Previous Page - Next Page