GPU 101 · Guide

What is GPU as a service?

A clear guide to cloud GPUs: what they are, training vs inference, orchestrated vs bare metal, and how to choose a GPU cloud without overcommitting.

~7 min read · written by the Baysn team

AI runs on GPUs, but very few teams should buy them. This guide explains what GPU as a service is, the choices you'll face, and how to rent exactly the compute you need without signing a multi-year contract.

Why AI runs on GPUs

A GPU, graphics processing unit, was built to do thousands of simple calculations at once. That happens to be exactly what neural networks need: enormous numbers of matrix multiplications running in parallel. A CPU does a few things very fast and in order; a GPU does thousands of things at once. For training and running AI models, that parallelism is the difference between minutes and weeks.

The catch is that the best AI GPUs are expensive, scarce, power-hungry, and obsolete faster than you'd like. Buying a cluster means a seven-figure outlay, a data-center contract, and a depreciating asset. That's why most teams rent.

What is GPU as a service?

GPU as a service (GPUaaS) means renting high-performance GPUs over the cloud instead of buying them. You get access to accelerated compute on demand, by the hour, the month, or the cluster, and the provider handles the hardware, the data-center, the networking, power, cooling, and maintenance. You bring the workload; they bring the machines.

The one-line version

GPU as a service is renting AI supercomputing by the hour instead of buying it, so your money goes into your model, not into depreciating hardware.

Training vs inference compute

GPUs do two very different jobs, and they shape what you rent. Training is building or fine-tuning a model, long, intensive runs that often need many GPUs wired tightly together with fast interconnects. Inference is running a finished model to serve requests, usually smaller, steadier, and latency-sensitive.

Training tends to want big, tightly-coupled clusters for bursts of time. Inference tends to want right-sized, always-on capacity. A good GPU cloud lets you do both in the same place, train a model, then serve it, without moving your data around.

Orchestrated vs bare metal

When you rent GPUs, there are two ways to receive them:

Most teams should start orchestrated and only drop to bare metal when they have a specific reason. The compute is the same either way; the difference is how much of the plumbing you want to own.

Pricing and commitments

GPU cloud is usually priced per GPU-hour, sometimes discounted for reserved or committed capacity. The trap to avoid is the multi-year lock-in: GPUs improve fast, and committing to today's hardware for three years can leave you paying premium rates for aging silicon. The smarter posture is the shortest commitment that still gets you the capacity and price you need.

Watch for

Long contracts on fast-moving hardware. The shortest commitment that secures your capacity protects you from being stuck on yesterday's GPUs at tomorrow's prices.

How to choose a GPU cloud

Question
What to look for
Why it matters
Availability
A confirmed start date
A waitlist is not capacity
Commitment
Short, flexible terms
Hardware ages fast
Orchestration
Slurm / K8s managed
Productive on day one
Path to serving
Train & infer in one place
No data migration

In short: pick a provider that can actually give you the hardware now, on terms short enough to stay flexible, with orchestration handled for you and a clean path from training to serving.

Frequently asked questions

Should I buy GPUs instead of renting?

Rarely, and only at very large, steady scale where you can keep expensive hardware fully utilized for years. For almost everyone else, renting avoids the capital outlay, the data-center burden, and the risk of being stuck on aging silicon.

What's the difference between GPU cloud and inference as a service?

GPU cloud rents you the machines to run whatever you want. Inference as a service is a managed layer on top, you call a model through an API and the provider runs it for you. Many teams use both: rent GPUs for training, use an inference API to serve.

Do I need Slurm or Kubernetes experience?

Not if you use an orchestrated offering, the provider runs the scheduler and you just submit jobs or deploy containers. You only need deep infrastructure skills if you take bare metal.

How fast can I get capacity?

With a provider that holds real inventory, days, not the months a hyperscaler waitlist can take. Always ask for a confirmed start date rather than a place in a queue.

Need GPUs on short terms?

Latest-gen capacity, orchestrated or bare metal, shortest commitments in the market