Path: bloom-picayune.mit.edu!snorkelwacker.mit.edu!americast.com!americast.com!americast-post Newsgroups: americast.ibd From: americast-post@AmeriCast.Com Organization: American Cybercasting Approved: americast-post@AmeriCast.com Subject: Computers & Automation Date: Mon, 9 Nov 92 12:21:57 EST Message-ID: <8.1992Nov9.122158@AmeriCast.com> 11/9/92 TITLE Computers & Automation PC Pointers: How To Select The Microprocessor That Fits Your Needs Brian Deagon Buying a personal computer has never been easier on the pocket- book - or harder on the brain. With prices plummeting every quarter, PCs are very affordable. But with hundreds of models to choose from, the hard part is choosing which one to buy. The decision to buy a computer is usually based on ease of use and screen quality. But these features are influenced by the quality of the computer's microprocessor, which is probably the most important choice to make before buying. The microprocessor is the central processing unit, or Computers & Automation "brain," of every personal computer. Choosing one used to be rather simple. Five years ago, PC buyers only had two basic choices if they were going to buy an IBM-compatible machine. They could buy a PC with Intel Corp.'s 80286 microprocessor or, for a lot more money, buy one with Intel's faster 80386 chip. Two years ago, buyers who wanted premium performance had three choices: two versions of the 386, one of which had its math coprocessor disabled, or the speedy new i486. Since then, Intel has adopted something like a carpet-bombing approach to micropro- cessor distribution strategy - filling every market hole with a custom chip. Intel's new marketing approach was spurred by competition. Four companies now offer microprocessors compatible with the Intel ar- chitecture: Advanced Micro Devices Inc., Cyrix Corp., Texas In- struments Inc. and International Business Machines Corp. Comput- er buyers now can choose from more than 15 microprocessors. The result is just as fortunate as it is confusing. Potential buyers should know, for example, whether a fully func- tional 386dx running at a clock speed of 33 megahertz is a better choice than a stripped-down 486sx running at only 25 megahertz. Answer: It depends on how the computer will be used. Here's a brief rundown on some basic chip differences to help narrow the options: The Power Misers. Computers are power hogs, a particular prob- lem for those who want to take their machines on the road and operate them on batteries. So about four years ago, Intel began building chips specifically for portable computers. In the past, portables often operated less than three hours on a single charge. Older chips tried to improve battery life by shutting off disk drives, screens and other components after a minute or two of nonuse. But that sometimes caused the computer to freeze up. The best portables to buy contain microprocessors with the "sl" designation. Computer chips like the Intel 386sl are designed with a "system management mode" that can shut down parts of the computer without inciting conflicts with the operating system, thereby increasing battery life to at least four hours. All the major portable PC makers offer sl models. Start- ing next year, also look for "low voltage" sl-chip portables, which will run on 3.3 volts or less, instead of five volts. Rulers Of The Desktop. Here, the issue is whether to choose a 386 or the next-generation 486. In most cases, even the lowest- grade 486 chip will outperform the fastest 386. But computer speed is also influenced by what else is inside. With extra com- puter memory, a fast disk drive and video enhancement board, a midrange 386 computer can blow the doors off a poorly designed 486. Hence, a good 386 computer may have all the power that's needed, particularly for the home user. Nonetheless, there is a compelling reason to consider the 486, especially for the busi- ness user: It's the best chip for the future. Not only do 486- based computers run a broader range of software applications fas- ter, but most of them can be upgraded by plugging in a companion 486 chip that, in some cases, will double the speed of the origi- nal system. Moreover, because of price wars, the cost difference between comparable 386 and 486 systems is so small that it's really worth spending a few extra hundred dollars for the 486. That being the case, expect PC manufacturers to discount their 386 systems even further, making them ideal for the first-time buyer. This year, for the first time, 386 computers went on sale for under $1,000. First-time buyers also will be confused by computers with sx and dx microprocessor designations. Chips with the sx designation are generally the same as the dx variety, ex- cept that the internal math coprocessor has been disabled, which makes them less expensive. Users who want high-quality graphics and plan to run power- hogging applications like Windows should go with the dx variety. For people on tight budgets who are mainly interested in using their PCs for word processing or other types of basic computing, the sx works fine. They should still, however, aim for the highest megahetz chip rating they can af- ford. The Speed Kings. Intel's follow-on to the 486 chip line - formerly known as the P5, or the 586 - is now called the Pentium. Shipments will begin in the first quarter. Novice PC users need not apply. Buying a PC with a Pentium would be like upgrading from a Toyota to a Fer- rari. For users who don't do a lot of number crunching, the Pen- tium chip will run 40% to 80% faster than Intel's top-end 486, the 66-megahertz, dx2 model. When the Pentium arrives, it likely will cause manufacturers to drop prices on their 486 computers. In many respects, Intel is moving into new territory with the Pentium. It will compete against comparable chips from Sun Microsystems Inc., Silicon Graphics Inc., IBM, Hewlett-Packard Co. and Digital Equipment Corp. Products in this range aren't even referred to as personal computers. They are called workstations or servers. This article is copyright 1992 Investors Business Daily. Redis- tribution to other sites is not permitted except by arrangement with American Cybercasting Corporation. For more information, send-email to usa@AmeriCast.COM