Sir Alan Sugar has left his role as chairman of Amstrad, the technology company he founded in 1968 at the age of 21.

Self-made multi-millionaire Sir Alan may be more famous as the star of BBC reality show 'The Apprentice', but he amassed his fortune building Essex-based electronics firm Amstrad. During the 1980s Amstrad was floated on the stock market and became one of the major players in the UK PC market, but its market share fell away and the company has recently struggled to make an impact in the consumer space.

These days Amstrad's main business is building set-top boxes for Sky TV. BSkyB bought the company in 2007, making Sir Alan's departure inevitable.

Sugar said it is the "right time" to go, but that he isn't retiring. As well as his TV work, Sir Alan has a large property portfolio and other businesses such as Amshold, Amsprop, Amsair and Viglen computers. Sir Alan is believed to be worth around £830m.

"The past 40 years have seen Amstrad grow from a start-up business to the success story that it is today, which is credit to the talented and loyal team here," said Sir Alan.

"This is a move that has been planned for a while and it's the right time for me to step down from my role at Amstrad," he added.

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