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U. Glaeser

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TABLE 4.1 Selected Categories of Computers<br />

Start Year Price Level $ Computer Category Typical Usage<br />

1990 1.0E+<br />

00 Disposable computer Smart cards, greeting card music generator, telephone SIMs<br />

1975 1.0E+<br />

01 Embedded processor Disk drive controller, automobile engine controller<br />

1990 1.0E+<br />

02 PDA Contact list, schedule, notes, calculator<br />

1980 1.0E+<br />

03 Personal computer Word processing, spreadsheets, email, web browsing, games<br />

1975 1.0E+<br />

03 Workstation Computer aided design and engineering, animation rendering<br />

1965 1.0E+<br />

03 Minicomputer Dedicated, or general computing for one user<br />

1985 1.0E+<br />

04 Workgroup server General computing support for a small group of people<br />

1955 1.0E+<br />

05 Departmental server Computing support for a large group (about 50–500 people)<br />

1970 1.0E+<br />

06 Enterprise server General computing support, interactive and network services<br />

1960 1.0E+<br />

06 Mainframe Corporate databases, transaction processing<br />

1970 1.0E+<br />

07 Supercomputer Nuclear weapons simulation, global challenge problems<br />

The changing price-performance is seen in different ways: improved performance at the same price;<br />

same performance at a lower price; or, both improved performance and improved price. A ten-fold<br />

improvement in price-performance often gives a qualitative change that results in a different product<br />

category. For example, computers can be categorized in different ways, such as those given in Table 4.1.<br />

The price-performance of software is not discussed in this chapter. Software creation is mainly a laborintensive<br />

activity. Therefore, the cost of creating software has been related to the cost of manpower, which<br />

is related to the rate of inflation. Some companies have outsourced software development to countries<br />

with lower labor rates, such as India. The second main factor in the cost of software is the number of<br />

people who buy a package. More sales result in lower costs for PC versions of software compared to<br />

software used on less common (bigger) computers.<br />

Price<br />

The price and performance of a computer system appear to be easily definable items. But, neither price<br />

nor performance is well defined. Price is often adjusted historically for inflation. Price is often quoted in<br />

a specific currency. In global markets, changing currencies can affect pricing of components and products.<br />

In this chapter, the prices are given in United States dollars ($) and are not adjusted for inflation.<br />

Pricing is dependant on sales factors, such as discounts, marketing agreements, customer categories,<br />

etc. The size of the market for a product is also important for costs. Quantities affect the price based on<br />

writing off of development costs over the number of units, cost of setting up production lines, setting<br />

up maintenance and training operations, etc. Generally, computers or general technologies that are<br />

produced in large quantities are cheaper at the same performance level than less popular items.<br />

A separate but important pricing issue is the difference between the entry price and unit pricing. For<br />

example, consider big disk drives versus floppy disk drives. The low entry price of a floppy disk drive opened<br />

a new market for low performance, high unit price (dollars per megabyte, or $/MB) floppy drives. Big highspeed<br />

hard disk drives were more expensive to purchase, but were much lower in unit costs of $/MB.<br />

Computer systems are a collection of component parts, such as the CPU, memory, storage, power supply,<br />

etc. The cost of a computer system depends on the choice of the components, which change with time [5].<br />

Performance<br />

The performance of computer technology depends on what you want the computer to do. Computers<br />

that are used for text processing do not need floating-point operations. Scientific computing needs heavy<br />

floating-point computation and typically high memory bandwidth.<br />

Standard benchmark programs often exhibit a 2:1 performance range on a single computer. One<br />

comparison of the execution times of different benchmarks run on two specific computers gave performance<br />

ratios ranging from 0.54 to 17295 [6]. Performance is also dependent on the quality of the compiler<br />

or interpreter, the algorithms used, and the actual source language programs. The sieve of Erasothenes<br />

© 2002 by CRC Press LLC

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