Intel CEO Paul Otellini unexpectedly revealed that he intends to step down from the company and retire in May 2013. The Intel board had expected Otellini to remain as CEO until he reached age 65 and only “reluctantly” accepted his resignation. Otellini is 62.

No reason was given for Otellini’s early departure, beyond the fact that it was initiated by the CEO. Otellini has been with Intel for 40 years and will have been CEO for 8 years when he does retire.

"After almost four decades with the company and eight years as CEO, it’s time to move on and transfer Intel’s helm to a new generation of leadership," Mr. Otellini said. "I look forward to working with [Intel board chairman] Andy [Bryant], the board, and the management team during the six-month transition period, and to being available as an advisor to management after retiring as CEO."

Otellini presided over an important era for Intel, during which it essentially vanquished its only major foe in the market for desktop and server chips, and helped Apple make the transition from the rival PowerPC platform. But Otellini was slow to embrace the mobile computing wave that is sweeping the industry, and the firm's chips for mobile devices have fallen behind rival designs based on ARM. This is doubly troubling given the sales slowdown in the PC industry.

Like earlier Intel CEOs, Otellini was promoted from within, though he wasn't an engineer like Robert Noyce, Gordon Moore, and Andy Grove. But Intel is now expected to at least consider an outsider for the CEO role—a move that would be a first for the company.

Intel reported that it generated $107 billion in cash from operations and made $23.5 billion in dividend payments during Otellini's tenure as CEO so far. Intel currently enjoys 83 percent market share in the PC market.

(Read about Otellini's criticism of Windows 8 here.)