(Reuters) - Chipmaker AMD said Chief Operating Officer Lisa Su would replace Rory Read as chief executive, effective immediately, sending the company's shares down 5 percent in extended trading.
Read, also the president of the company, is stepping down as part of a transition plan, AMD said in a statement.
AMD, a perennial runner-up to Intel Corp in the business of providing processors for personal computers, named Read as CEO in August 2011. Since then, AMD's market value has nearly halved as the company lost more market share to Intel.
AMD has been expanding into new markets such as game consoles and low-power servers, but selling PC chips remains its main business for now.
Su, 44, joined AMD in 2012. As chief operating officer, she handled product strategy, execution, sales and operations.
AMD said its board was discussing with Su the terms of her employment. She is currently paid an annual base salary of $650,000, the company said.
Read, 52, will remain with the company in an advisory role until the end of the year.
AMD's shares were trading at $3.11 after the bell. Up to Wednesday's close, the stock had fallen 15 percent this year.
(Reporting by Soham Chatterjee in Bangalore; Editing by Kirti Pandey)