Well, this is unexpected. AMD has announced that Rory Read, who’s served as CEO since August 2011, has stepped down. The company’s board has chosen Dr. Lisa Su, its former Chief Operating Officer, to replace him—"effective immediately."

SUNNYVALE, CA–(Marketwired – Oct 8, 2014) – AMD (NYSE: AMD) today announced that its board of directors has appointed Dr. Lisa Su as president and chief executive officer and member of the board of directors, effective immediately. Dr. Su, 44, succeeds Rory Read, 52, who has stepped down as president and chief executive officer, and member of the board of directors, as part of a transition plan. Read will support the transition in an advisory role, remaining with the company through the end of 2014. "Leadership succession planning has been a joint effort between Rory and the board and we felt that Lisa’s expertise and proven leadership in the global semiconductor industry make this an ideal time for her to lead the company," said Bruce Claflin, chairman of AMD’s board of directors. "The board looks forward to continuing to work with Lisa and the rest of the senior management team to build on the company’s momentum. I would also like to thank Rory for his many accomplishments and contributions positioning AMD for long-term success by helping to create a strong foundation and clear path to re-establish the company’s growth and profitability."

In the press release, Su is quoted as saying, "I look forward to expanding on the strong foundation we have built under Rory’s leadership as we develop industry-leading technologies and products for a diverse set of markets to drive sustainable and profitable growth."

AMD plans to shed more light on this development in a conference call later today.

The change of leadership comes after continued financial struggles for the chipmaker. Although it posted its first profit in over a year thanks to the arrival of the PlayStation 4 and Xbox One last October, AMD was in the red again earlier this year, with net losses of $20 million and $36 million in the first and second quarters of 2014, respectively. Nonetheless, AMD says Read’s leadership has seen it make "significant progress in financial and operational performance," with operational expenditures down 30% and cash reserves at "near an optimal level of $1 billion" since 2012.

Update 5:01 PM: Now that the AMD conference call is over, we have a somewhat clearer sense of what unfolded today and why.

For starters, Read made it clear that Su has been groomed to succeed him as CEO from the start. Addressing the timing of the change, Read said, "The part I’m good at, I’ve already done." The former CEO explained that Su’s more product-centric background makes her a better candidate to steer AMD through the next phase of its transformation, which will involve, among other things, the ramp-ups of Project Skybridge and the K12 architecture.

Su also outlined her goals for AMD’s future, which don’t sound too different from those Read had already set. AMD’s "highest priority" will be to "build great products," she said. The company will also seek to forge more "strategic relationships with market leaders" as it’s already done with Sony and Microsoft for the current crop of consoles. Finally, Su said she will "continue to simplify the company and speed up [its] execution."

Read plans to stay on as an adviser to Su and AMD for the time being. No new COO has been named; instead, Su will incorporate her former duties into her new job.

Update 6:16PM: Here’s our take on why this transition took place.