fter a period of neglect, the intellectual legacy of Seymour Cray, the father of the modern supercomputer, is being revived.

The scientists in government, industry and academia who are engaged in the race to build the world's fastest computing machines are now turning their attention once again to Mr. Cray's elegant approach to building ultra-fast computers.

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When Mr. Cray died after a car accident in 1996, the one-of-a-kind machines that embodied his computing philosophy had gone out of fashion, largely replaced by designs based on thousands of connected microprocessors that are inexpensive and mass produced.

Mr. Cray's custom machines are known as vector supercomputers and have special hardware that is intended to handle the long strings of numbers in complex scientific computing problems. The machines are highly regarded for a design that balanced computing speed and the ability to transfer data extremely rapidly within the computer while the calculation is taking place.

This design philosophy is being revitalized by Burton J. Smith, a founder and the chief scientist of the Seattle-based Tera, which bought the original Cray Research in 2000. In the three years since the acquisition, Mr. Smith has been seen in the industry as the most prominent champion of Mr. Cray's approach.

"The pendulum swung way too far," Mr. Smith said of the research and attention given to the microprocessor approach to supercomputing.

For the first 25 years of supercomputing, Mr. Cray's machines held the title of "faster computer in the world." But beginning in the late 1980's, the entire computing world became subject to what became known as the "attack of the killer micro."

Instead of specialized hardware, along the lines of Mr. Cray's designs, these rival computers rely on microprocessors — with hundreds, and then thousands, and then tens of thousands of microprocessors lashed together to make ever-faster supercomputers.

Known as "massively parallel processors," or M.P.P. machines, these computers rapidly took over the supercomputer market, gaining popularity in research and weapons laboratories.

Looking back, the arrival of M.P.P. machines was a product of government policy.

Up until the 1980's, the United States government viewed supercomputing as part of its technological competition with the Soviet Union and Japan, heavily subsidizing research and development. But with the end of the cold war, federal support evaporated because of a lack of strategic urgency and a belief that M.P.P. machines proved that supercomputing could prosper with components derived from the consumer computing industry.

Today, the M.P.P. designs are proving to have limits, a fact made obvious last year when a Japanese supercomputer built in the Cray tradition by NEC Electronics Corporation won the computing speed crown.

Now there is a emerging consensus among American computer designers that the Lego-block approach of chaining together microprocessors fails when it comes to certain classes of computing problems.

"There's a buzz in the air," said Jack Dongarra, a University of Tennessee computer scientist who tracks the world's fastest 500 computers. Scientists and computer designers have been trying to convince the government agencies of the need to invest in designs in the tradition of Mr. Cray, he said. "We're crossing our fingers."

According to a number of scientists, the real issue, outlined in a National Science Foundation committee report this year, is too little investment in advanced computing technologies. A similar report from the Defense Department and a report soon to be released by the National Academy of Science echo that theme.

In hearings before the House Science Committee last month, supercomputing experts put forward a case for a significant increase in federal spending on supercomputing, citing their relevance to counterterrorism projects and scientific research.

This refocus is underscored by supercomputer experts who said that JASON, an elite group of scientists who perform studies for the Pentagon, is investigating shortcomings in the military-financed Advanced Strategic Computing Initiative, which relies heavily on massively parallel computers.

There is a growing concern that the billion-dollar program, which is intended to monitor the nation's nuclear stockpile and simulate weapons explosions, has been a disappointment because the M.P.P. computers used by the project have proven inefficient and difficult to program.

The Cray approach is now seen as a natural alternative. Cray Inc., the name Tera took after purchasing Cray Research, last month reported strong revenue and profits for its second quarter of 2003. Revenue for the quarter was $61.8 million compared with $38.6 million for the same quarter last year. Net income was $7.9 million, or 10 cents a share, up from $1.2 million, or 2 cents a share, reported in the second quarter of 2002.

The company's stock, which had been as low as $3.05 in the last 12 months, ended last week at $11.21.

Cray's revival was helped last month when the company became one of three computer makers, along with I.B.M. and Sun Microsystems, chosen by the Pentagon's Defense Advanced Research Projects Agency to develop prototypes of next generation of supercomputers that can reach peak speeds of a petaflop — quadrillion mathematical operations per second — by the end of this decade.

Cray had been in decline since the late 1980's. The company was purchased by SGI in 1996 for $740 million, a move that some Cray designers have referred to as "the occupation."

SGI put an end to the Cray vector supercomputer line, but was forced to resurrect it several years later when the National Security Agency indicated a need for the traditional machines. The agency financed the development of a new class of supercomputer called the X1, which the company introduced last year.

In 2000, the company was sold again, this time to Tera, a company founded by Mr. Smith and his partner James Rottsolk. While Mr. Cray was known as a hardware-packaging genius, Mr. Smith, a 63-year-old math expert, has a reputation as a remarkably inventive computer designer.

He was a pioneer of the concept of multithreading, a technique that is widely used today in modern microprocessors to add parallelism and to make more efficient use of hardware resources.

At the company, Mr. Smith's vision is matched with the pragmatism of the chief architect of the Cray X1, Steve Scott, say scientists who have worked with both men.

"At Cray, Burton serves the role of the idea person," said Bill Dally, a Stanford computer scientist who has been a consultant to Cray over many years. "He's always coming up with very creative, very bold ideas."

Mr. Dally said that the two men work well together, with Mr. Scott being more practical and down to earth. "It's a good match," he said.

A crucial part of Mr. Smith's success has been his ability to create a company that can remain viable in a business where product design and development can take decades. "I have this idea of the manifest destiny of computers," he said in explaining why he is motivated to persist in the business. They are the only tools, he said, that "truly leverage the power of the human mind."

When Mr. Smith and Mr. Rottsolk founded their company in 1987, they chose Seattle because it was a place that did not have the intense hothouse culture of Silicon Valley. The company's headquarters, where 120 of Cray's 900 employees work, is in Pioneer Square, in the heart of the city's historic district.

One indication of a shift away from M.P.P. design is that Thomas Sterling, a computer scientist at the California Institute of Technology, and Mr. Smith's consultant in the design of the new supercomputer, was the creator of a particular class of inexpensive massively parallel computers known as Beowulf clusters that can be assembled from off-the-shelf personal computers.

Mr. Sterling acknowledged that while those cheap machines solve many problems there are computing challenges that will require fundamental new designs like the new Cray machine, called Cascade, that may reach a petaflop sometime near the end of this decade.

It will take that kind of computing speed, for example, to simulate all the effects on an airplane wing as it moves through the atmosphere: the flapping of the wing, turbulence and the changing temperature of the wing. Mr. Sterling said it was not yet proved whether Mr. Smith's new machine would be able to meet this kind of challenge.

"He is simply one of the brightest guys about all aspects of computing that I've met," Mr. Sterling said. "The problem here is that Burton's legacy will be determined by his impact."