The graphics chip maker announces that Jack Tseng has resigned as president, chief executive, and chairman.
Vice chairman and company founder John Gibbons, 59, will assume Tseng's titles, the company said.
Gibbons has served in several senior executive management positions at Tseng since 1989, most recently as executive vice president and chief operating officer.
Jack Tseng agreed to vote or to authorize a person designated by the board to vote all common shares for which he had voting power.
The company last month said it is cutting staff by 20 percent to 30 percent and is taking a one-time charge of $500,000 to $1,000,000 in its fourth quarter for related severance programs.
Tseng also has hired investment banking firm Broadview Associates to "explore strategic alternatives."
Reuters contributed to this story.