Andy Grove. Anne Knudsen/Getty Images Andy Grove, Intel's former CEO, died on Monday at the age of 79. The exact cause of his death was not disclosed, but he's been battling Parkinson's disease for years.

Intel announced his death in a statement.

Grove was Intel's first hire in 1968 and played an instrumental role in taking the company from a scrappy startup to the most powerful chipmaker in the world.

His leadership at Intel spans nearly 40 years, being named the company's president in 1979 and CEO in 1987. He remained as the company's chairman until 2004.

It was under Grove's watch that Intel formed the famous "Wintel" duopoly with Microsoft that dominated the PC market. Intel increased annual revenues from $1.9 billion to more than $26 billion under Grove's management.

But it's Grove's relentless work ethic and bruising management style that have earned the respect of many followers. Steve Jobs used to call Grove his mentor, while Marc Andreessen often says that Grove's the man who built Silicon Valley.

His book, "Only the Paranoid Survive," is still considered a must-read management book by many business leaders.

"We are deeply saddened by the passing of former Intel Chairman and CEO Andy Grove. Andy made the impossible happen, time and again, and inspired generations of technologists, entrepreneurs, and business leaders," Intel CEO Brian Krzanich said in a statement.

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