Turing Award Winner: TPUs vs GPUs vs CPUs, Computer Architecture, RISC vs CISC

Turing Award winner David Patterson explains the RISC vs CISC debate from the 1980s, covering why RISC won (3-4x speedup, simpler compiler optimization, energy efficiency), how ARM became dominant across mobile and cloud, and why CISC's sophisticated instructions were rarely used by compilers. He then explains the architectural differences between CPUs, GPUs, and TPUs: CPUs are general-purpose, GPUs evolved from graphics with multithreaded architectures and became useful for ML due to fast floating-point, and TPUs were purpose-built by Google for matrix multiplication in neural networks — achieving 30x better inference than GPUs and 80x over CPUs. Patterson also discusses Moore's Law slowing down, Dennard scaling ending around 2005, the shift to domain-specific architectures, NVIDIA's CUDA moat, and the MLPerf benchmarking effort.