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What: Shares of Advanced Micro Devices (NYSE: AMD) have plunged today by as much as 10% after CFO Thomas Seifert abruptly resigned.

So what: Seifert also served as AMD's interim CEO last year, after the board gave ex-CEO Dirk Meyer the boot for lacking a mobile strategy. Eventually, Rory Read was named CEO. AMD pointed out that Seifert's resignation wasn't based on any issues with the company's financials.

Now what: In addition, another executive, Chris Cloran, general manager of client products, is calling it quits. The move calls into question AMD's turnaround, as the company has been flailing for quite some time. Seifert will stay on until the end of the month to help with transitioning to a new CFO. For a more detailed breakdown of events, don't miss fellow Fool Anders Bylund's take.

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Fool contributor Evan Niu holds no position in any company mentioned. Check out his holdings and a short bio. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Try any of our Foolish newsletter services free for 30 days. The Motley Fool has a disclosure policy.