Apple this "past summer" canceled the development of a high-performance Mac chip that would have consisted of four smaller chips stitched together, in order to free up engineering resources for a planned AI server chip, according to The Information.
Based on the report's description of the chip, it sounds like Apple has canceled a previously-rumored "Extreme" chip for the Mac. It was previously reported that an "M2 Extreme" chip was scrapped a few years ago, but perhaps Apple had revisited the idea since then. In any case, it now sounds like an "M4 Extreme" chip is also unlikely.
Apple likely would have introduced the "M4 Extreme" in its high-end Mac Pro tower. The chip would have offered even faster performance than the M4 Ultra chip that is expected to launch in new Mac Studio and Mac Pro models later next year.
If the "M4 Extreme" were to have been a quadrupled version of the M4 Max chip that debuted in the MacBook Pro a few months ago, it would have had massive specifications, including up to a 64-core CPU and up to a 160-core GPU.
While the "Extreme" chip may be off the table once again, it seems like Apple has repeatedly shown interest in developing such a chip, so perhaps it will eventually materialize as part of the M5 series or later. For now, though, the wait continues.
Update: After this story was published, Daring Fireball's John Gruber made a good point about how there is a long, multi-year gap between Apple designing and shipping new chips. Accordingly, it is possible the latest chip canceled actually would have been an "M5 Extreme" chip or later if development was only recently ended.
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