Shares of Advanced Micro Devices shot up as much as 4% in early trading on Monday, the latest mystery move in a stock that has been buffeted by rumors in recent weeks.
The chipmaker’s shares, up 21% so far this year, have largely been gaining over the past two years as CEO Lisa Su’s turnaround strategy has begun to take off. Dumping the company’s previous strategy of coming out with lower-priced chips that appealed mainly to budget buyers, Su put the company on a multi-year path to revamp its PC, server and graphics chips with a focus on much greater performance improvements.
But since hitting a high of $15.65 in February, just as the first of Su’s new chip lines went on sale, the stock price has largely bounced between $10 and $14. In mid-morning trading on Monday, the shares were at $13.69. Recent rumors have included a deal to license graphics chip designs to Intel (intc), supply a proprietary chip for future Tesla (tsla) Model 3 electric cars, or be bought outright by Google (googl). The first two appear to be false, while the takeover makes little sense.
On Monday, the only public news about AMD was negative. Chief market strategist at TD Ameritrade Joe Kinahan told the Wall Street Journal that AMD and competitor Nvidia (nvda) were vulnerable if the price of cryptocurrencies like bitcoin and ethereum dropped, because it could depress demand for the graphics cards made by the two companies that are often used to mine them.
“You could see their stock prices very quickly collapse” in the event of a bubble bursting, Kinahan said about AMD and Nvidia.
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Shares of Nvidia were up 3% on Monday, while Intel shares were about unchanged.
On Monday, the price of bitcoin rose, but few bitcoin miners rely on graphics cards from AMD and Nvidia anymore, preferring specially designed chips known as application-specific integrated circuits, or ASICs, which are made by smaller chipmakers. And the prices of ethereum and other cryptocurrencies that commonly are mined using graphics cards were down on Monday.
An AMD (amd) spokesman had no comment on the stock move on Monday.