- Shopping Bag ( 0 items )
Get Up To Speed for Windows ...
Ships from: acton, MA
Usually ships in 1-2 business days
Get Up To Speed for Windows XP and Server 2003 Training-Fast!
MCSA/MCSE 2003 JumpStart gives you the solid grounding you need to approach MCSA and MCSE certification training with confidence:
process v : to complete a series of actions
Every computer consists of a microprocessor and memory. Without the two, the computer would not function. The microprocessor, commonly referred to as the Central Processing Unit (CPU), is the brain of the computer. Like the human brain, the CPU is responsible for managing the timing of each operation and carrying out the instructions or commands from an application or the operating system.
The CPU uses memory as a place to store or retrieve information. Memory comes in several forms, such as random access memory (RAM) and readonly memory (ROM). Memory provides a temporary location for storing information and contains more permanent system configuration information. This chapter provides an overview of these topics related to microprocessors and memory:
Processor performance Processor types History and evolution of Intel processors Intel's competition-AMD, Cyrix, PowerPC, and Alpha Multiprocessor computers Physical memory Bus architecture and bus types
The most central component to the computer is the processor. It is responsible for executing the instructions that are given to the computer. The processor determines the operating systems you can use, the software applications you can run on the computer, and the computer's stability and performance. It is also typically one of the major factors in computer cost. Computers that contain newer and powerful processors are more expensive than computers with less complex processors. This has led processor manufacturers to offer several different lines of processors for the home user, business workstation, and server markets.
The goal of processor performance is to make applications run faster. Performance is commonly defined by how long it takes for a specific task to be executed. Traditionally, processor performance has been defined as how many instructions can be completed in each clock cycle, or instructions per clock (IPC) times the number of clock cycles. Thus, performance is measured as:
IPC x Frequency
Processor Types: A First Look
So many types of computer processors, also referred to as microprocessors, are on the market today that it can be quite confusing to wade through them all. All processors are not created equal, and each processor has its own characteristics that make it unique. For instance, a processor that is built around an architecture common to other processors of the same time period may actually operate at double or triple the speed. Fierce competition among the various chip makers lays the groundwork for new technological innovations and constant improvements.
The most obvious difference among processors is the physical appearance of the chips, meaning that many processors differ noticeably from one another in size and shape. The first processor that Intel released was packaged in a small chip that contained two rows of 20 pins each. As processor technology improved, the shape and packaging scheme of the processor also changed. Modern processors, such as the Intel Pentium 4 class processors, use an advanced packaging scheme in which the processor is encased in a single-edge cartridge (SEC) module that plugs into a slot on the motherboard. Much like an expansion card that easily plugs into the motherboard, the SEC module can easily be removed and upgraded. This design also reduces the cost involved in producing the CPU.
Another noticeable difference among processors is the type of instruction set they use. The instruction sets that are most common to processors are either Complex Instruction Set Computing (CISC) or Reduced Instruction Set Computing (RISC).
CISC has been a common method of processing operations, especially in Intel CPUs. CISC uses a set of commands, which include subcommands that require additional CPU memory and time to process. Each command must go through a decode unit, located inside the CPU, to be broken down into microcode. The microcode is then processed one microcode at a time, which slows computing.
RISC, on the other hand, uses smaller commands that enable it to operate at higher speeds. The smaller commands work directly with microcode, so there is no need for a decode unit. This factor-along with a RISC chip's capability to execute multiple commands simultaneously-dramatically increases the processing power.
Finally, different manufacturers design processors to varying specifications. You should be sure that the processor type and model you choose are compatible with the operating system that you want to use. If the processor is not 100 percent compatible with the operating system, the computer will not operate at its best or might not work at all.
The terms processor, microprocessor, chip, and CPU are used interchangeably.
Deciphering Processor Terminology
For most computer novices, terms such as microcode efficiency and internal cache RAM can sound like part of a foreign language. To help you keep things straight, here are some common terms and their definitions:
Clock cycles The internal speed of a computer or processor expressed in megahertz (MHz) or gigahertz (GHz). The faster the clock speed, the faster the computer performs a specific operation.
CPU speed The number of operations that are processed in one second.
Data path The number of bits that can be transported into the processor chip during one operation.
Floating Point Unit (FPU), or math coprocessor A secondary processor that speeds operations by taking over math calculations of decimal numbers. Also called a numeric processor.
Level 1 (L1), or internal, cache Memory in the CPU that is used to temporarily store instructions and data while they are waiting to be processed. One of the distinguishing features of different processors is the amount of internal cache that is supported.
Level 2 (L2), or backside, cache Memory that is used by the CPU to temporarily store data that is waiting to be processed. Originally located on the motherboard, CPU architectures such as the Pentium II, III, and 4 have incorporated L2 cache directly on the same board as the CPU. The CPU can access the on-board L2 cache two to four times faster than it can access the L2 cache on the motherboard.
Microcode efficiency The capability of a CPU to process microcode in a manner that uses the least amount of time and completes the greatest number of operations.
Word size The largest number in bits that can be processed during one operation.
All the computer's components, including the processor, are installed on the motherboard. This fiberglass sheet is designed for a specific type of CPU. When purchasing a motherboard, you should check with the motherboard manufacturer to determine which types of CPUs are supported.
The Intel Processor Lineup
Over time, Intel has introduced several generations of microprocessors. Each processor type is referred to as a generation; each is based on the new technological enhancements of the day. With each product release come new software and hardware products to take advantage of the new technology.
Several generations of Intel processors are available today. Since the arrival of the first Intel chip in the IBM PC, Intel has dominated the market. It seems that every time you turn around, a new chip promises greater performance and processing capabilities than the previous one.
What makes Intel the market leader is its ability to bring the newest innovations in chip technology to the public, usually before its competitors, who are not far behind. Competition is fierce, and each manufacturer attempts to improve on the designs of the others, releasing similar chips that promise better performance.
The following table shows the specifications for the Intel processors issued to date. You should read the specifications and reviews of each processor to understand its capabilities and reliability.
Factors Affecting Performance
Many factors come together to determine the performance of any computer. All other factors being equal, faster components will give better performance, but any computer will be limited by its "weakest links." As an analogy, consider that putting a larger engine in a standard automobile will make it faster, but only if the automobile is going in a straight line. As soon as you try to make the car follow a twisting road, other components such as the drivetrain and the tires can limit the performance of the larger engine.
Within a processor family, faster processors will outperform slower processors. But when we're comparing processors from different families, that rule does not apply. For example, the rating of 400MHz for a processor from one family does not indicate that it will run significantly faster than a 333MHz processor from a more advanced processor family.
As you learned earlier, clock cycles and data path are two factors that can influence the performance of your computer. Other factors are:
Cache memory Very fast memory that sits between the CPU and the main RAM. Cache memory can be as fast as 5 to 10 nanoseconds, whereas main RAM is usually not faster than 60 to 70 nanoseconds. (Yes, a lower number is better here because it indicates that the memory takes less time to move data.)
Bus speed The rate at which data can be transferred between the CPU and the rest of the motherboard. Typical bus speeds are 733MHz and higher with the current standard for motherboards entering the market.
The type of peripherals on your computer can affect system performance. If your application spends a lot of time accessing your hard disk, selecting a better-performing disk system would improve CPU efficiency. For example, Small Computer System Interface (SCSI) hard disks place a much smaller overhead burden on your CPU than Integrated Device Electronics (IDE) storage devices. Storage systems are covered in detail in Chapter 2, "Storing Your Files: Data Storage."
History of Intel Chips
Intel released the world's first microprocessor, the Intel 4004, in 1971. It was a 4- bit microprocessor containing a programmable controller chip that could process 45 instructions. The 4 bits meant that the chip had four lines for data to travel on, much like a four-lane highway. Because of its limitations, it was implemented only in a few early video games and some other devices. The following year, Intel released the 8008, an 8-bit microprocessor with enhanced memory storage and the capability to process 48 instructions.
Intel then began to research and develop faster, more capable processors. From that research emerged the 8080, which could process instructions 10 times faster than its predecessors. Although the speed had dramatically improved, it was still limited by the number of instructions it could process. Finally, in 1978, Intel broke many barriers by releasing the first of many computer-ready microprocessors, the 8086. The 8086 was a breakthrough technology with a bus speed of 16 bits and the capability to support and use 1MB of RAM. Unfortunately, the cost of manufacturing such a chip and compatible 16-bit components made the chip unaffordable. Intel responded the following year with the production of an 8-bit chip, the 8088.
Intel continued to break new ground as the release of each new generation of processor offered improved functions and processing capabilities. The most dramatic improvement was the number of instructions, based on a scale of millions, that the processor could process in one second. This rate, referred to as millions of instructions per second (MIPS), ranges from 0.75MIPS for the 8088 to over 450MIPS for Pentium 4 processors.
The second most dramatic improvement was the speed of the internal clock, measured in megahertz. All processors are driven by an internal clock mechanism that keeps the rhythm of the chip, much like the rhythm of a heartbeat. The faster the speed of the internal clock, the faster the processor can process instructions. Intel continued to increase the speed of the internal clock from 4.77MHz for the original 8088 to more than 2.2GHz for the newest generation of Intel microprocessors.
The First Generation: 8086 and 8088
The first major processor release from Intel was the 8086 microprocessor. The processor debuted as the first evolutionary step in a multitude of processors, each improving on the design of the original 8086. The lineage is referred to as the x86 family of microprocessors. Although this first release was crude compared to today's standards, it paved the way for the others to follow.
The 8088 was released a short time after the 8086 but was not as powerful as its predecessor. The 8086, a true 16-bit processor, contained 16-bit registers and a 16-bit data path. Motherboard technology had not quite reached the 16-bit level and was still costly in 1981. IBM decided to use a version of the 8088 chip, with the same design but with an 8-bit data path to accommodate the widely used 8-bit technology of the time.
The Second Generation: 80286
Intel forged a new milestone in PC processor technology with the release of the 80286, more commonly called the 286. The 286 offered a significant performance increase over the 8086 and 8088 with the unique capability to operate in a protected mode. The protected mode enabled the processor to multitask and still included its normal, or real, mode of operation. The Computer's Brain: Processors and Memory
Real mode required memory to be accessed in a linear format. This means that data being sent to RAM had to be placed in the order it was received-one application after another. With this limitation, instructions were usually processed one at a time.
Protected mode enabled multitasking to occur by allocating a specific range within memory for each task. Applications could therefore be accessed simultaneously, greatly improving performance.
Some companies produce upgrades for 286, 386, and 486 computers. The processor upgrades are relatively inexpensive and can greatly improve the overall CPU speed. Although 286 upgrades are nearly impossible to find, upgrades for 486-based computers are available. The processor upgrade can convert your aging 486 into a speedy computer, comparable to a Pentium.
The Third Generation: 80386
Intel's introduction of the 80386 processor reached yet a new milestone, condensing more than 250,000 transistors onto a single 32-bit processor chip. (The number of transistors on a processor is an indicator of the complexity of the processor and of its ability to perform complex calculations.) This new generation of processors incorporated true, fully functioning multitasking capabilities. Protected mode was now commonly referred to as the 386 Enhanced Mode, because the 80386 was able to overcome the multitasking limitations of the 80286.
The 80386 included a new operating mode called Virtual Real Mode. This new mode created conventional memory space required by DOS programs to run within the Windows operating system. Virtual Real Mode, or Virtual DOS Mode as it is commonly called, is still used for running DOS-based games and applications within Windows 95 and 98.
You will learn more about DOS and Windows operating systems in Chapter 5, "Desktop Operating Systems: A Comparison," and Chapter 6, "DOS 101: DOS Basics Every MCSA and MCSE Should Know."
Several types of 80386 chips were issued, each with a unique combination of features. Intel offered two options: the 80386DX and the 80386SX CPUs. Both were 32-bit processors, but the 80386DX used a 32-bit data path and the 80386SX used a 16-bit data path. Although the SX chip had smaller data paths, it was more competitively priced.
The Fourth Generation: 80486
Like the 80386, the next family of processors was released in 80486SX and 80486DX versions. Both included a 32-bit internal and external data path and an original internal clock frequency of 33MHz. The SX version was released with the numeric processor, or FPU, disabled and the internal clock speed slowed to 20MHz to offer a lower-cost processor to the consumer. Later this became a limitation with the emergence of more powerful software applications. A numeric processor was issued to complement the SX, turning it into a fully functioning DX.
A dramatic improvement was engineered into later deployments of the processor. A mechanism called a clock doubler enabled the internal system clock to run at twice the normal bus speed. Soon the 486DX-33 became the 486DX2-66, with the 2 signifying the clock-doubling technology. Eventually the idea of increasing the clock speed led to a clock tripler.
Excerpted from MCSA/MCSE 2003 JumpStart by Lisa Donald Excerpted by permission.
All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
Excerpts are provided by Dial-A-Book Inc. solely for the personal use of visitors to this web site.
|Ch. 1||The Computer's Brain: Processors and Memory||1|
|Ch. 2||Storing Your Files: Data Storage||27|
|Ch. 3||Data Movement: Input/Output Devices||59|
|Ch. 4||Hardware Configuration||81|
|Ch. 5||Desktop Operating Systems: A Comparison||95|
|Ch. 6||DOS 101: DOS Basics Every MCSA and MCSE Should Know||111|
|Ch. 7||Graphical Interface: Windows Basics||139|
|Ch. 8||A Communications Framework||163|
|Ch. 9||Network Models||183|
|Ch. 10||Data-Link and Network Layer Protocols||199|
|Ch. 11||Network Operating Systems: A Comparison||221|
|Ch. 12||Windows Server 2003 Origins and Platforms||233|
|Ch. 13||Windows Server 2003 Active Directory||247|
|Ch. 14||Account Management||267|
|Ch. 15||File and Print Management||281|
|App. A: Answers to Review Questions||305|
|App. B: Glossary||317|
|App. C: Common Acronyms||335|