NEW YORK, Aug. 24 -- AMD's biggest artificial-intelligence customer can buy up to 160 million AMD shares. At Monday's price that option covers about $73 billion of the company, roughly a tenth of it, and it was written into the same agreement under which OpenAI committed to deploying six gigawatts of AMD accelerators.

That is an unusual way to sell chips, and it is the fact worth holding onto while reading Monday's tape. AMD fell 3.38 per cent to $457.25 in the early afternoon in New York, one of the worst performers in a semiconductor complex that was down across the board. The Philadelphia Semiconductor Index dropped 2.83 per cent and now sits 22.2 per cent below its 52-week high. AMD itself is 21.8 per cent off its own.

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