Mark Dean: Co-inventor of the Personal Computer

February 11, 2020

This profile on Mark Dean is the fifth post in a month-long series of profiles on Black STEM innovators in honor of Black History Month. Today’s post also celebrates Safer Internet Day, by focusing on Mark Dean, co-inventor of the personal computer because without the computer, there would be no internet. Read the next profile in the series which focuses on Angela Benton, Tech Entrepreneur.

Many important inventions were made so long ago in the past that they are taken for granted such as paper in the second century, vaccines in 1796, and refrigeration in the 1850s, to name a few1. With these and many other pivotal inventions as part of human’s normal day, the internet may be the modern equivalent of these life-changing inventions. But how did we get to the internet? We started with the personal computer.

Enter the computer scientist and engineer you’ve never heard of – Dr. Mark Dean.

Since he was a child Dean always loved to build contraptions and had an aptitude for school. Both of these proclivities stayed with Dean through high school where he graduated with straight-As, during his time at the University of Tennessee where he graduated from the top of his class with a B.S. in Electrical Engineering in 1979, and throughout his career with the International Business Machines Corporation (IBM)2.

Dean began his career at IBM as an engineer only a short time after graduating from college. Together with his colleague, Dennis Moeller, Dean developed a new technology that allowed support devices to be directly connected with a computer, which he called the Industry Standard Architecture (ISA) systems bus. The ISA greatly increased the integration of technology while simplifying the setup required to have multiple devices, such as disk drives, printers and monitors, talk to a computer. After this invention, Dean also provided valuable research and work that culminated in the first color PC monitor. While the ISA and the color monitor were great breakthroughs for Dean and his career, his real success came in 1999.

In 2000, Dean worked with a team of IBM’s engineers to create the first gigahertz chip, a microprocessors able to do a billion calculations a second, and break the barriers of what microprocessor manufacturers and semiconductor engineers thought was possible5.

An article published in 2000 by The New York Times reported “the demands of the Internet and electronic commerce ensure a voracious market for all the speed and performance the chip makers can deliver. The first big market for gigahertz processors will likely be Web servers.”

Despite the race to a gigahertz processer Dean found himself in the midst of as IBM and Intel insisted that they were the first company to create this processes, Dean remained focused on furthering the capabilities of technology and increasing diversity in the workplace.

"I ignored the people attempting to block my progress and had no limits to who I talked to and in sharing my opinion," Dean said in a 2015 interview with Engadget. "I also was able to demonstrate my ideas to a point where it was hard to argue their viability. It took a lot of work and sacrifice. But I was confident and believed I had some good ideas. Fortunately, there were a few in the right leadership positions that agreed with my ideas.6"

In this same interview, Dean shared words of wisdom for the next generation of job applicants.

"If someone is blocking your ideas and advancement, find a different way to expose your proposals, innovations and request," he told Engadget. "There is often someone at the next level or an associate manager that is willing to listen. To break through, you often have to be better than the rest. This takes a lot of work, but it is achievable. I would also suggest young people consider emerging areas of opportunity: bio-engineering, civil engineering, nano-technology, analytics, security, sensor technology, material science.6"

Dean never did let anyone stop him from achieving his success and went on to earn a master's in electrical engineering from Florida Atlantic University in 1982 and a Ph.D. in Electrical Engineering from Stanford University in 19924.

For his revolutionary work, Dean holds three of IBM’s original nine patents3. He also invented the Industry Standard Architecture system bus with engineer Dennis Moeller, allowing for computer plug-ins such as disk drives and printers. Dean was the first African American ever to be named an IBM fellow in 1996, and in 1997 was honored with the Black Engineer of the Year President's Award, and inducted into the National Inventors Hall of Fame. In 2001, he was tapped to be a member of the National Academy of Engineers2.

Dean may not be a household name, but his legacy still lives on in household products.


  1. The Atlantic. (2013, November). The 50 Greatest Breakthroughs Since the Wheel. Retrieved from
  2. Biography. (2020, January 15). Mark Dean. Retrieved from
  3. National Inventors Hall of Fame. (2020). Mark Dean. Retrieved from
  4. The University of Tennessee Knoxville. Office of Research & Engagement. Retrieved from
  5. The New York Times. (2000, February 7). New Era Approaches: Gigahertz Chips. Retrieved from
  6. Engadget. (2015, February 6). Mark Dean designed the first IBM PC while breaking racial barriers. Retrieved from