What Is an NPU?
Every accelerator in this section so far has been a variation on "more programmable cores, running in parallel." An NPU (neural processing unit) is a different move entirely: instead of adding parallel general-purpose lanes, it removes almost all of the general-purpose machinery and replaces it with a dataflow of multiply-accumulate (MAC) cells wired specifically for tensor arithmetic. CPU vs GPU vs NPU already introduced this as the third design point; this page works through what that design point actually buys and what it costs.