The Von Neumann Bottleneck (1945-Present)
1945-PresentWhat Happened
John von Neumann's 1945 computer architecture separated processing from memory, connecting them via a bus. As processors accelerated dramatically—60,000x faster over 20 years—memory bandwidth improved only 100x. By 1977, John Backus described the problem in his Turing Award lecture, calling it the von Neumann bottleneck. Today, AI systems spend 500 times more energy moving data than computing with it.
Outcome
Cache systems and separate memory paths provided temporary relief through the 1990s-2000s.
The bottleneck became critical as AI emerged, forcing development of processing-in-memory, compute-in-memory, and novel memory technologies to break the architectural limitation.
Why It's Relevant Today
Altermagnetism attacks the same problem from a different angle—faster, denser memory that reduces the gap between processing speed and memory bandwidth that's strangling AI.
