Mark Dean
In a career spanning more than three decades, Dean contributed to pivotal technologies that helped shape the information age
Mark Dean, arms folded in a windowed hall

At-home computing went mainstream in 1981 when IBM introduced its mass-market 5150 “IBM PC” to the world. In 1998, a computer processor designed in the company’s Austin Research Lab reached 1 billion cycles per second (1GHz). Six years later, the Blue Gene supercomputer clocked in as the fastest in history. There’s a common thread across these technology landmarks —  Mark Dean, an IBM engineer whose innovations and leadership helped shape the information age.

Dean once said that his career evolved in seven-year cycles. Between his work on the PC and the 1GHz chip, he earned his PhD in electrical engineering from Stanford University, returning to IBM after a three-year hiatus to continue in a vocation punctuated by periodic marquee breakthroughs. Along the way he earned accolades from his employer, recognition and profound respect from his peers, and a place in the history books of computing technology. 

Project Chess and the IBM PC

From an early age Dean excelled at math. As a first grader growing up in Jefferson City, a small town in eastern Tennessee, he tutored older kids in trigonometry. By middle school, he decided he wanted to be an engineer, and in high school he resolved to work in computers for IBM, he told The Bent, a publication of Tau Beta Pi, the oldest engineering honor society in the US. Later, while on scholarship at the University of Tennessee, he laid the groundwork for his eventual career at the company.

Dean joined IBM in Boca Raton, Florida, in 1979 just after graduating college with highest honors. His first project was developing a word processor adapter for IBM’s Data Master, an attempt at creating a lower-cost computer for small business that combined word and data processing capabilities. He soon earned a spot on the secretive “Project Chess” team of engineers tasked with building a computer for the home. “Back when I started at IBM, the company let us do something people would think was ridiculous — create a PC,” Dean said.

The IBM PC changed consumer computing, fueled nearly a decade of market share dominance for the company, and yielded to Dean three of his dozens of patents. Two of his three PC-compatible patents were for adapters for monochrome and color graphics. His work would lead to the development of the color PC monitor. “IBM has made a lot of money that came out of that work,” he said. “We had a significant role in opening up patents license as a business.”

Back when I started at IBM, the company let us do something people would think was ridiculous — create a PC Mark Dean IBM Fellow
The AT bus and the dawn of a peripherals industry

Dean’s biggest contribution, perhaps, in the PC’s early days spawned a whole new ecosystem of IBM-compatible peripheral devices. The AT bus, or later the Industry Standard Architecture (ISA) bus, was a means of connecting components to a computer’s processor and enabling communication among them. Soon it became a much simpler matter to connect and manage printers, video cards and external disk drives. IBM wanted companies to design for its PC, and by sharing a standard approach, it stoked development of third-party, PC-compatible products.

Originally designed to support the Intel 8088 processors inside IBM’s first-generation PC, the ISA was later adapted from an 8-bit to a 16-bit version and gained wide acceptance in 1984. A group of competitor companies manufacturing PC clones would go on to extend the ISA from 16 to 32 bits and co-opt it as the“open” industry standard as IBM migrated to a different, proprietary bus architecture.

While little about IBM’s first PC was homegrown — it was created mostly with off-the-shelf parts — three of the nine patents related to the original PC belonged to Dean. He was named head of all PC design at 25 years old.

3 of the 9 patents related to the original PC belonged to Dean. He was named head of all PC design at 25 years old.
The first Black American IBM Fellow

From the mid-to late-1990s, Dean earned many accolades and added another pivotal achievement to an already stellar list of inventions.

In 1995, the company named Dean an IBM Fellow, a designation Thomas J. Watson Jr. established in 1962 as the “pre-eminent technical distinction, granted in recognition of outstanding and sustained technical achievements and leadership in engineering, programming, services, science, design and technology.” Dean was the first Black American to earn the title. In 1997, he was named Black Engineer of the Year, and the National Inventors Hall of Fame elected Dean and colleague Dennis Moeller for their work on the ISA bus.

That same year, Dean became director of IBM’s Austin Research Laboratory, set up in 1995 to focus on advanced circuit design and developing new techniques and tools for high-performance microprocessors. Soon after, the company announced a breakthrough invention from the Austin lab — the first experimental CMOS processor (which stores Basic Input/Output Settings) that could operate at 1 billion cycles per second, or 1,000MHz/1GHz, a speed almost unthinkable then but today a standard for the internet age. Before then, the fastest processors operated at speeds of less than 300MHz.

Blue Gene
The world’s fastest supercomputer

After his time leading the Austin lab, Dean worked in various research positions and in 1999 assembled a small team of engineers and scientists to work on building a more powerful, energy-efficient supercomputer named Blue Gene. Two years later, the company spun up a second Blue Gene project to run simultaneously. “Our initial exploration made us realize we could expand our Blue Gene project to deliver more commercially viable architectures for a broad customer set and still accomplish our original goal of protein science simulations,” said Dean, who by then was vice president of Systems at IBM Research.

Roughly USD 100 million and five years later, IBM unveiled Blue Gene, ushering in a new era of high-performance computing. Developed and manufactured in collaboration with the US Department of Energy’s Lawrence Livermore National Laboratory, Blue Gene was the most powerful and most efficient supercomputer, consuming just a fraction of the power and floorspace of any other supercomputer. On September 29, 2004, it surpassed NEC’s Earth Simulator as the fastest computer in the world. In 2009, President Barack Obama recognized the Blue Gene family of supercomputers with the National Medal of Technology Innovation, the country’s most prestigious award for technology achievement.

In 2004, Dean was offered a position running the company’s Almaden Research Center in California, where its 400 researchers included experts in database and storage technology. After Almaden, Dean became vice president of worldwide strategy and operations for IBM Research and later was CTO of IBM’s Middle East/Africa business. Once asked about his leadership style, Dean said he thinks of himself as someone who helps others get things done — an attitude echoing a disposition Thomas Watson Sr. impressed on his managers years ago. 

Dean left IBM in 2013 to lead a whole new generation of engineers, returning to the University of Tennessee to become the John Fisher Distinguished Professor in its College of Engineering.

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