The following points summarize the key concepts in this chapter.
- The CPU (central processing unit)—a microprocessor—is the centerpiece of today's computers.
- Clock speed is only one determining factor in identifying overall performance of a processor.
- Processors are generally defined by their speed, the size of the external data bus, and the size of the address bus.
- The development of the 80286 processor introduced the concepts of real and protected modes and allowed the use of up to 16 MB of memory.
- The development of the 80386 processor brought about 32-bit processing and allowed up to 4 GB of memory.
- The 80486 processor is a souped-up version of the 80386 and introduced the use of cache memory.
- The Pentium chip began a new line of processors and technology, incorporating RISC and true multithreading capabilities in an Intel microprocessor for the first time.
- The Intel Pentium III further extended PC performance with advanced cache technology and streamlined code handling.
- Today's standard processor is the Pentium III, with processor speeds of 500 MHz and greater.
Replacing and Upgrading Chips
- It is important for a computer technician to know the technological advances made by each successive generation of computers.
- Simply upgrading the CPU can often lengthen the lifespan of a computer.