This leads Berlin into a conundrum in her first book, “The Man Behind the Microchip: Robert Noyce and the Invention of Silicon Valley.” For the last 40 years, Noyce, a founder of Intel, has been famous as “the inventor of the integrated circuit,” that infinitesimal sliver of silicon and metal that forms the core of a computer’s brain. This achievement was so remarkable that Noyce (1927-90) was hailed in the press for decades, awarded a National Medal of Science by President Carter, and made wealthy.

An inspiring tale! Except for one thing: Noyce didn’t singlehandedly invent the integrated circuit. Texas Instruments produced a working model years before Intel did; and even when Noyce’s company finally released its rather superior chip, it was a team of Noyce’s employees who did the hands-on and theoretical work, with Noyce serving mostly as inspiration and administration. “Noyce had almost nothing to do with building the device,” Berlin herself concludes. This is not to say that Noyce is an unworthy subject of a book; he’s quite intriguing. But trying to write a biography of a guy who didn’t do what he’s most famous for gently bedevils Berlin, and her book morphs inadvertently into a sort of detective story: precisely what did Robert Noyce actually do?

One thing is certain: Noyce was a prodigy in the study of transistors. Transistors, the first step in the modern computer age, were invented in 1947; and William Shockley, John Bardeen and Walter H. Brattain shared the 1956 Nobel Prize in physics for the achievement. Transistors worked like little electronic off-on switches: put voltage in one way, and the transistor would amplify the signal; send it in the other way, and it would shut the flow down entirely. Everyone could see how useful these devices would be, but the physics of how transistors worked were poorly understood. At M.I.T., Noyce in his 20’s became a groundbreaking expert.

He quickly drew the attention of Shockley, who hired him to help make specialized transistors for military and business-machine companies like I.B.M. This is where Berlin is best: she superbly evokes the hacker inventiveness of Shockley and his gang. Their work was more alchemy than science; they’d shove transistors in furnaces and bombard them with chemical fumes, with few clues as to what would work. (The engineers referred to these processes as “witches’ brew” and “black magic.”) Shockley was a character of almost necromantic strangeness: an egomaniac who insulted his staff (“Are you sure that you actually went to school?” Berlin paraphrases a characteristic assault) and at one point became convinced a competitor had planted a booby trap in his lab. After nearly two years in which Shockley was unable to forge a corporate direction, his brilliant central group left en masse to found Fairchild Semiconductor.

They picked Noyce to lead them. He radiated a mix of laid-back calm and confidence rare among engineers, which served him well in the commercial deal-cutting that made them all rich. Noyce hated confrontation: he preferred to give his brainy employees wide latitude to pursue oddball projects, convinced that smart nerds would always wind up doing something interesting and valuable. His distaste for conflict eventually destroyed his marriage; unable to grapple with the unhappiness of his wife, who, university educated and born to a wealthy New England family, was slowly driven mad with ennui by her child-centered suburban life, he retreated into a risky affair, which ended when one of his children actually found his mistress in bed with him. At work, though, Noyce’s surfer disposition formed the perfect bridge between his prickly geeks and the bean-counting business world that relied on transistors. “Your charisma is scary,” an assistant told him. “Use it wisely.”

As for the integrated circuit? Noyce had a legitimate “aha” moment. In early 1959, a Fairchild engineer showed him a clever way to cram several transistors together on one silicon wafer. Inspired, Noyce sketched out an elegant design for a single chip that could add numbers. In a flash, he had developed the basic idea behind the microchip, a concept that to this day empowers every computer.

But then he jammed his notes in a drawer and forgot about them. He wasn’t prodded to action until two months later, when Texas Instruments announced it had created a working prototype of an integrated circuit. Noyce’s lawyers panicked; he quickly filed for a patent on the concept. And that is how Noyce wound up getting credit for the microchip, even though the courts awarded Texas Instruments four patents and Noyce one. Noyce, the most telegenic chip wizard, got the lion’s share of the attention.

He rather charmingly professed hardly to care who got the glory. That is easy to believe; his eye was always on the next thing. He left Fairchild to found Intel, where he persuaded dubious colleagues to produce the first programmable computer chip for the mass market. Unfortunately, once the microchip drama is over, Berlin’s spirited storytelling becomes bogged down in business minutiae, and the book fades.

Noyce fades, too. He slowly disconnects from Intel’s everyday affairs, sublimating into a sort of Asimovian figure. Mostly, his role seemed to be giving blindingly sunny talks about the future — a disposable computer! intelligent braking systems on cars! — while leaving his Intel co-founders to figure out the messy details.

Perhaps that was his true genius. One could argue that Noyce was less important for pioneering the chip than for pioneering the psychology of Silicon Valley. Pick any cliché of today’s high-tech C.E.O. behavior, and Noyce forged the template. He bought and flew his own planes; played the extreme sports of his age; handed out employee stock options while fighting unions; relished his instant wealth, yet continually nursed a Puritanical suspicion that nobody could ever deserve that much bling. His follow-your-bliss management style set the tone for many Valley success stories, most notably today’s young founders of Google, who encourage their employees to tinker with projects that might seem simply goofy. As Noyce realized, it is those flights of fancy that leave the world a permanently different place, no matter who gets credit for that.

Clive Thompson is a contributing writer for The New York Times Magazine.