Definition: GPU

(Graphics Processing Unit) A programmable processor specialized for rendering 3D images on a Windows computer. NVIDIA is the leader in the field by a large margin (see NVIDIA). However, AMD and Intel also make GPUs, and Apple, Qualcomm and ARM integrate GPU circuits into mobile devices.

Graphics circuitry can be included with other functions in the PC's chipset or even on the CPU chip itself. However, for gamers, the stand-alone graphics card with a GPU that plugs into a PCI Express (PCIe) slot on the PC motherboard is essential (see below). See chipset.

A GPU is all about performing parallel operations. Although it is used for 2D data as well as for zooming and panning the screen, a GPU is essential for rendering 3D animation. The more sophisticated the GPU, the higher the resolution and the faster and smoother the motion. See graphics pipeline.

Streaming Multiprocessors
An NVIDA GPU can have more than a hundred Streaming Multiprocessors (SMs), which are its primary processing units. Each SM contains thousands of CUDA cores along with registers, schedulers and shared memory. For non-NVIDIA GPUs, Compute Units (CU), Workgroup Processors (WGP) and Xe Cores are equivalent to the SM. See CUDA.

Ray Tracing Engine
A GPU may also include hardware to accelerate ray tracing, which simulates a light source falling on objects to create bright areas and shadows. Fast ray tracing enhances realism and has become mandatory for serious gaming (see ray tracing).

The Engines Behind AI and Crypto
A GPU is a "math machine" that performs huge amounts of simple calculations simultaneously making it ideal for AI applications that require trillions of computations (see neural network and AI training passes). GPUs are also used to mine certain cryptocurrencies (see GPU mining).

GPUs Are Often Integrated With the CPU

Introduced in 2012, AMD's Trinity chip integrated a GPU with memory (DDR3) and two dual-core x86 CPUs, each with their own L2 cache (see x86, L2 cache). (Image courtesy of Advanced Micro Devices, Inc.)

GPU and Everything Else

In 2020, Qualcomm introduced the Snapdragon 888 system-on-chip (SoC). Along with a GPU, this single chip does just about everything for a smartphone. See Snapdragon and SoC.

Graphics Evolution in a Windows PC

On the left is the evolution of graphics circuits with 7 being the latest. On the right is performance with 1 being the fastest. Gamers plug in the fastest GPU card they can afford, and high-end graphics can cost more than the entire PC (see RTX)..

Blame It on Gamers!

Had gaming with 3D images not been such a force around the turn of the century, NVIDIA would not have been compelled to make high-end video cards with GPUs that would get faster every year. The enthusiasm for 3D games enabled AI to flourish by the 2020s.