GPU (Graphics Processing Unit)

In short

A specialized computer chip that can perform thousands of calculations simultaneously, making it essential for training and running AI models.

A regular processor (CPU) is like a single brilliant mathematician who can solve any equation, but only one at a time. A GPU is like a stadium full of 10,000 average calculators, each solving a simple equation simultaneously. AI workloads are like grading 10,000 multiple-choice exams — you don’t need a genius, you need a lot of people working at once.

AI models need to perform billions of mathematical operations — multiplying huge tables of numbers together. A GPU can do thousands of these multiplications in parallel. That’s why training a model that might take months on a regular processor can take days or hours on GPUs.

The dominant GPU maker for AI is NVIDIA. GPU costs are a major driver of AI expenses — renting a single high-end GPU in the cloud runs roughly $2–4 per hour. Training a frontier model can cost tens of millions of dollars in GPU time. This is also why running your own open models requires serious investment.

GPUs are used for both phases: Training (teaching the model, extremely compute-heavy) and Inference (running the trained model, less intensive but still benefits from GPUs). The cost and availability of GPUs is one of the main reasons why AI development is concentrated among a handful of large companies.