The Next Major Battleground

By Philip Elmer-DeWitt

Silicon Valley has not seen such a bumper crop since it stopped growing peaches and prunes and began producing computer chips. Hardly a week has gone by this spring without a ballyhooed announcement of a new semiconductor or a line of high-speed computers. At the center of the excitement is a new breed of microprocessors that promises to give computer manufacturers their biggest performance boost in a decade. Lightning fast, the chips make it possible to put the power of ten to 20 refrigerator-size minicomputers into a single desktop-size machine.

Of all the announcements, none has generated as much anticipation as the one to be made this week by Motorola, the largest U.S. supplier of semiconductors (1987 sales: $6.7 billion). The electronics giant has etched 1.7 million transistors into a three-chip microprocessor called the 88000 that it hopes will become a standard component of the next generation of high-performance computers. Motorola may be right. Even before the new product was formally unveiled, more than 30 prospective customers, including Data General, | Convergent and Tektronix, had formed a users group to set guidelines for designing hardware and software to take advantage of the new chips. Says Motorola Vice President Murray Goldman: "This is the next major battleground in the computer world."

How do the new chips achieve their performance breakthroughs? In a word: RISC, for reduced instruction set computer. RISC is not a new technology, but a fresh approach to computing that challenges 25 years of semiconductor design. It focuses on a computer's most basic commands: the instructions that are embedded, or hard-wired, into the silicon circuitry of the machine's central processing unit. The first computers made do with a handful of primitive commands, such as LOAD, ADD and STORE, which programmers combined to perform complex tasks. Lacking a command to multiply 6 times 5, for example, they had to instruct their computers to add five 6s together.

Over the years, the basic instruction sets grew in length, as miniaturization allowed computer designers to etch more circuits into silicon chips. The most advanced microprocessors began to resemble state-of-the-art calculators that could compute everything from square roots to compound interest at the touch of a button. By the time Digital Equipment introduced its best-selling VAX 11/780 computer in 1977, the machine's instruction set had swelled to 304 commands.

But the increased complexity had its cost. Studies showed that 20% of the instructions were doing 80% of the work. The rest were like expensive extras on a limousine: rarely used luxuries that took up space and slowed performance. The advocates of RISC, declaring that it was time to go back to basics, stripped away the nonessentials and optimized the performance of the 50 or so most frequently used commands. Says Ben Anixter, vice president at Advanced Micro Devices, a Sunnyvale, Calif., firm that is introducing its first RISC chip in two weeks: "It is like going from the complicated old piston airplane engine to the turbojet."

At first, the industry was reluctant to switch to RISC. But the new crop of chips has made believers out of almost everybody. Sun, a company best known for its engineering computers, got into the chip business last summer when it began licensing a RISC processor to AT&T, Unisys and Xerox. MIPS, which introduced its second generation of the chips last month, supplies microprocessors to Tandem, Prime, and Silicon Graphics. Hewlett-Packard has built an entire line of computers around RISC technology.

Most important, IBM is making a major commitment to RISC. IBM Vice President Andrew Heller suggests that RISC technology could produce startling advances in electronic speech recognition, machine vision and artificial intelligence -- all of which require superfast microprocessors. Says Heller: "Computers that can listen and talk back, and recognize objects on sight, are not so farfetched. RISC will help make all that a reality, and it's going to happen this century."

With reporting by Thomas McCarroll/New York and Edwin M. Reingold/Los Angeles