Apple’s new paralleling chip architecture may have addressed some of the inefficiencies of multiple chips.
Apple’s UltraFusion, the name of its packaging technology, uses a narrow silicon slice called an interposer that resides beneath the two M1 Max chips, linking them with 10,000 wires that can carry 2.5 terabytes of data per second over a very short distance. That enormous speed is necessary so chip cores on one die can reach memory that’s connected to the other. Graphics processing units in particular have an insatiable appetite for data stored in memory.
For more, check out this c|net story.