Technology startups can be filled with big egos and difficult personalities, but those who worked with Doug Pihl remember him as thoughtful and supportive of other people's ideas and pleasant to be around.

Pihl, who made thousands of local investors wealthy through pioneering Minnesota-based high-technology companies, died of cancer July 28. He was 81.

Pihl and his sister, Audrey, were raised in Minneapolis by father Carl-Oscar Malcolm Pihl, a tool maker at Honeywell, and mother Colona. Later cousin Mary Jane Johnson Olson also helped raise them after Colona Pihl was quarantined with tuberculosis.

Pihl graduated from Washburn High School, studied physics and engineering at the University of Minnesota and started his career with Minnesota's budding computer industry at Data Display, Data 100 and Control Data.

In 1979, Pihl entered the entrepreneurial world, starting Lee Data with some colleagues to make peripheral equipment for IBM's large computer systems. After several name changes, it eventually became part of networking software giant Oracle.

In 1990, Pihl founded NetStar, a computer networking equipment maker for supercomputers that also found uses for the emerging internet. Six years later the company was sold to California-based Ascend Communications for $300 million.

Later, Pihl became chairman of RocketChips, helping that company raise money and develop a high-speed communications computer chip. In was acquired by California-based Xilinx Inc. in 2000 for more than $200 million.

"He was always going for the big hit; he never wanted to do something in a small way," said Ron Thomas, who worked with Pihl for a number of years and served on some of the same boards.

"Every company he started, he was looking for some real groundbreaking products," he said.

Don Hall, a local investor and author, said Pihl was someone who got things done but also was "always thoughtful in what he said."

Investors did well by following Pihl.

"Doug developed a following as an engineer to start, but he made that transition from a successful engineer to a successful CEO," said John Feltl, CEO of Feltl and Co., a Minneapolis-based investment banking firm that backed many of Pihl's deals and countless more in the 1990s and early 2000s.

Feltl, who invested personally in Pihl's companies, reports that patient investors in RocketChips are still reaping rewards. Feltl said the RocketChips technology remains in a key Xilinx product line.

Stephanie Thomes, head of investment strategy for Allianz with a focus on alternative investments and startups, worked with Pihl early in her career at another of his startups, MathStar, from 1999 to 2004.

"He was a brilliant engineer and a savvy manager," Thomes said. "And there were two lifelong lessons he taught me: 'Be kind to your colleagues, and never ever stop learning.' "

Pihl also joined the board of Vital Images and later became board chairman and served as an interim CEO. According to founder Vincent Argiro, Pihl led the board's decision to refuse a lowball takeover offer from a big manufacturing company and, in 2011, sold to Toshiba in a much more lucrative deal that was valued at more than $200 million.

"He was so well known in the investment community that he was able to smooth the waters," Argiro said.

Pihl is survived by his wife, Jo, daughter Allison Pihl, son Todd Pihl, sister Audrey Hopkins and two grandchildren.

Services have been held.