Mubadala now owns a 19.9 percent share of AMD, Silverman said.

AMD on Monday also appointed Bruce Claflin as a chairman of the company's board of directors, replacing former chairman Hector Ruiz, who retired. Claflin has been a member of AMD's board of directors since 2003, AMD said. Ruiz will now be chairman of The Foundry Company's board.

AMD also announced Mubadala CEO Waleed Al Mokarrab to its board of directors.

AMD's shares were trading at US$2.02 in the after-hours of the stock market, down 7.8 percent.