Michael Dell, 39, CEO & Founder, Dell Computer ($17.95 billion)

Michael Dell, 39, Chairman and founder of Dell Computer, with a wealth of $17.95 billion, is America's richest man under the age of 40.

The Fortune magazine announced its annual list of the 40 richest Americans under the age of 40 on Wednesday.

Michael Dell has held the No. 1 spot since the list was started in 1999. He founded the Dell Computer Corporation in 1984. His company is the fastest-growing major computer systems businesses in the world.

The company is able to sell custom-built PCs directly to end users at a much cheaper rate as Dell has bypassed the middleman. The company's sales have zoomed to over $23.6 billion from $6 million when it first began selling computers.

Michael Dell has received several top honours, like 'Entrepreneur of the Year' from Inc. magazine, 'Man of the Year' by PC magazine, 'Top CEO in American Business' from Worth magazine, and 'CEO of the Year' by Financial World and Industry Week magazines. In 1997, 1998 and 1999, he was on Business Week's list of 'The Top 25 Managers of the Year.'

Photograph: HO/AFP/Getty Images

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