NPU vs. GPU: What’s the Difference?

Neural processing units (NPUs) and Graphics processing units (GPUs)
are two pieces of silicon found in many modern devices, including smartphones and desktop PCs. They can both accelerate machine learning and AI workloads, but the graphics processor’s primary role is in 3D rendering. Here are the other differences between these two common chips.

Both NPUs and GPUs are found alongside each other in a range of devices, though NPUs are less common than GPUs, since the latter is required in any device with a display of some sort. The two processors also perform different tasks.

A graphics chip is primarily used for 3D rendering, whether that’s your laptop’s home screen or your smartphone game. It can also accelerate AI workloads.

An NPU, however, is exclusively used to accelerate AI workloads.

GPUs can be part of a CPU or SoC, where they share the system memory with other components. However, they can also be standalone GPUs in laptops and tablets, or standalone add-in graphics cards in the case of desktop PCs. In those cases, the GPU has its own dedicated memory, called VRAM.

NPUs can also be built into a CPU or SoC, or standalone, but they always share the system memory and don’t have dedicated RAM.

Credit : https://www.lifewire.com/npu-vs-gpu-8692361