hardware · Level 3
Setting up a workstation or home server to run AI locally
A practical, honest buying guide: GPU and VRAM, PSU and cooling, and the workstation, laptop or home server trade-off, including the heavier case of local AI video generation.

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Start with the essentials
The short answer
The hardware that matters most for running AI locally is GPU memory, not processor speed. This workbook explains VRAM tiers, the real trade-off between a laptop, a desktop workstation and a home server, how to size a PSU and cooling properly, and why AI video generation needs substantially more VRAM than everyday local text or image use.
What you will learn
- You will be able to explain why VRAM, not processor speed, is the number that decides whether an AI model runs on a given machine.
- You will be able to choose honestly between a laptop, a desktop workstation and a home server for your own situation.
- You will be able to size a GPU against real VRAM tiers, for everyday local AI and for the heavier case of AI video generation.
- You will be able to size a PSU and plan cooling and case choices that actually make a GPU purchase work in practice.
- You will be able to draft a real, honest shopping list for your own budget tier, and know what to check before buying a used GPU.
Who it is for
Anyone comfortable buying and setting up ordinary computer hardware who is planning a workstation or home server to run AI models locally, from someone experimenting with local chatbots to someone who wants to generate AI video without renting cloud GPU time. No electronics or soldering skill is needed, just the willingness to read a spec sheet and open a case.
Before you start
- None beyond basic comfort buying and setting up a computer. Running open-weight AI models on your own computer, for free and The free AI toolkit: how to choose tools and stay safe cover the software and model side of local AI; this workbook is the hardware side those two assume you already have.
Learn in your browser · Chapter 01 of 07
The one number that matters most: VRAM
Before any purchase, it helps to know which single specification actually predicts whether AI runs well on a machine, and it is not the one most people check first.
Two computers with the same processor speed can behave completely differently when you try to run AI locally, because the number that predicts success is not CPU speed. It is VRAM: the memory built into your graphics card, or the memory pool your GPU can reach. A language model, an image generator or a video generator all load their weights into that memory before they can do any work, and if the model does not fit, nothing else about the machine matters.
There are three memory pools you will meet, and they are not interchangeable. VRAM sits on a dedicated graphics card: fast, and usually the smallest pool in the system, from a few gigabytes on an older laptop to well over twenty gigabytes on a high-end card. System RAM is larger and shared with everything else the computer is doing; running a model from system RAM on the CPU alone works but is generally much slower than a GPU. Unified memory, used by Apple Silicon Macs, is a single pool shared between the CPU and GPU, so a Mac with a large amount of it can sometimes hold a bigger model than a laptop with a similarly sized but separate VRAM pool, because the GPU can reach the whole pool.
This workbook covers two different jobs, and they need very different amounts of that memory. Running a local text assistant, the kind covered in Running open-weight AI models on your own computer, for free, is comfortable on a modest dedicated GPU, sometimes even on a laptop's built-in graphics for the smallest models. Generating AI video locally is a heavier job, covered properly in Chapter 5, and it is worth deciding early which of these you actually need, because it changes almost every choice that follows.
nvidia-smi --query-gpu=name,memory.total --format=csvTry it yourself · Activity 01
8 minFind your own numbers
Before you read any further, write down what you are actually starting from.
- Check your current machine's dedicated GPU memory, or unified memory if it is an Apple Silicon Mac, using the method above.
- Note whether it has a dedicated graphics card at all, since some laptops only have an integrated chip with no separate VRAM.
- Decide, honestly, whether your interest is local text and image AI, AI video generation, or both, since Chapter 5 treats video as a heavier, separate case.
Does your current machine already clear a sensible floor for what you want to do, or is this workbook genuinely about a new purchase?
Worked answer
Example: a gaming laptop with an 8 gigabyte dedicated GPU. That comfortably covers small local text models, per Chapter 2's table, but Chapter 5 will show it is well under what serious local video generation needs.
Learn in your browser · Chapter 02 of 07
Workstation, laptop or server: choosing the right shape
The same GPU can go into three very different kinds of machine, and the right shape depends on how and where you will actually use it, not just the specification sheet.
A laptop with a dedicated GPU is the only option if you genuinely need to carry the machine with you, but it pays a real price for that portability: laptop GPUs of the same name as a desktop card usually run at lower power and therefore lower performance, batteries do not like sustained heavy loads, and cooling in a thin case is a genuine limit on how hard you can push it for long. A desktop workstation trades portability for headroom: more room for a bigger GPU, better cooling, easier upgrades later, and no battery to protect. A home server, a machine left running permanently, usually headless, without its own screen, and reached over your network, is a different answer again: not primarily for interactive use, but for a model, an agent or a household AI tool that is always available, running around the clock.
Scroll sideways to see every column.
| Shape | Best for | Real trade-off |
|---|---|---|
| Laptop | Working on the move, trying things out without a dedicated space | Lower sustained performance for the same GPU name, and heat is a genuine limit |
| Desktop workstation | The best performance for interactive, hands-on work at a desk | Not portable, and needs a place with decent airflow |
| Home server | An always-on model, agent or household tool other devices reach over the network | Runs continuously, so noise, heat and running cost matter more than for occasional use |
Consider two different people. One works from a cafe some days and wants to draft with a local model wherever they are: a laptop with a decent dedicated GPU is the honest answer, even knowing it will run some jobs more slowly than a desktop would. The other wants a model or agent available to every device in the house at any hour, without a laptop staying open on a desk: a small always-on home server suits that better, even at lower single-job performance.
Try it yourself · Activity 02
10 minMatch your situation
Answer honestly, about how you actually work, not how you think you should.
- Do you need to physically carry this machine anywhere, regularly?
- Do you want it available around the clock, reachable from other devices, even overnight?
- How much does noise and running heat matter in the room this machine will actually live in?
- Would you rather spend more upfront for headroom, or start smaller and upgrade later?
Did your honest answers point at the shape you assumed you wanted, or somewhere else?
Worked answer
Example: someone working from a shared flat wants overnight availability but cannot tolerate a noisy machine in a shared living room. That combination points towards a smaller, quieter home server tucked away, rather than a loud high-end desktop kept on all night in a communal space.
Learn in your browser · Chapter 03 of 07
The GPU decision: what actually matters
Once you know the shape of machine you want, the GPU inside it is the single highest-leverage choice you will make, and VRAM is still the first number to look at.
Beyond VRAM, three things genuinely matter. Architecture and generation: a newer generation of the same brand's GPUs is usually more efficient per watt and per gigabyte, so a recent mid-range card can outperform an older high-end one. Software ecosystem: NVIDIA's CUDA platform has, for years, had the deepest and most consistent support across AI tools, which matters more than raw specification, since a card only helps if the software you want to run actually supports it well. AMD's ROCm and Apple's Metal and MLX have both improved, but coverage across AI tools is patchier and worth checking against the specific tool you plan to use. New versus used: a previous-generation card with plenty of VRAM, bought used, is often better value than a newer card with less, because running out of memory is a hard stop, not a graceful slowdown.
Scroll sideways to see every column.
| VRAM | Comfortable for | Genuinely tight for |
|---|---|---|
| 8 to 12 GB | Small to medium local text and image models, everyday assistant use | Larger local models, and, per Chapter 5, most AI video generation |
| 16 to 24 GB | Larger local text models, and short, modest AI video generation clips | Long or high-resolution video generation, running several tools at once |
| 32 GB and above, including workstation-class cards or a Mac with a large unified memory pool | Serious local video generation work, and running bigger models with headroom to spare | Very little, though cost rises steeply at this tier |
Two real shapes of GPU show the trade-off. A recent mid-range card with around 12 to 16 gigabytes of VRAM comfortably runs the small and medium local text models covered in Running open-weight AI models on your own computer, for free. An older but higher-VRAM card, or a Mac with a generously sized unified memory pool, can sometimes run a larger model than a newer card with less memory, simply because it has more room, even if each request runs more slowly. Capacity and raw speed are different numbers, and for whether something runs at all, capacity usually matters more.
Try it yourself · Activity 03
12 minSize a GPU for your own use case
Use the table above with the numbers you found in Chapter 1.
- Decide which VRAM tier you are honestly aiming for, based on whether you want text and image models, occasional light video generation, or serious video work.
- If you already own a GPU, find its exact VRAM from the manufacturer's own product page, not from memory.
- Note whether your planned software's own documentation lists your GPU brand as well supported, checked today, not from an old source.
Did checking the software support step change your answer, even after you had already picked a VRAM tier?
Worked answer
Example: someone aiming for AI video generation initially considered a 12 gigabyte card, then, checking Chapter 5's tier guidance and their intended tool's own current requirements page, revised that to a 24 gigabyte card before buying anything.
Learn in your browser · Chapter 04 of 07
Power, PSU and the rest of the build
A powerful GPU is only as good as the power, cooling and case around it, and this is where people who priced the GPU carefully still get caught out.
A PSU, power supply unit, has a maximum wattage it can deliver, and every GPU manufacturer publishes a recommended minimum system PSU wattage for that specific card on its own product page. Treat that published number as a floor, not a target: add the rest of your system's real draw, the CPU under load, drives, fans, and leave genuine headroom above the total rather than buying to the exact minimum. A PSU running constantly near its limit runs hotter, less efficiently and less comfortably than one with room to spare.
Cooling and the room the machine lives in matter more for AI work than ordinary use, because generation jobs can run a GPU flat out for minutes or hours, not short bursts. Check that your case actually fits the GPU's physical length before buying either one, that air can genuinely move through the case rather than just past it, and that the room has some ventilation: sustained heavy use puts out real, noticeable heat, worth planning for rather than discovering afterwards.
A GPU working hard draws meaningfully more power than one sitting idle, for as long as the job runs. That is a genuine ongoing cost alongside the purchase price, scaling with how much you actually use the machine, worth factoring into the budget tiers in Chapter 6 rather than only the price on the box.
Scroll sideways to see every column.
| Component | What people underestimate |
|---|---|
| PSU | The manufacturer's published minimum is a floor for that card alone, not for the whole system with headroom included. |
| Case | Whether the GPU's physical length actually fits, and whether air can move through the case, not just past it. |
| Cooling | How long the fans and airflow need to sustain a job running for minutes or hours, not a short burst. |
| Room | Sustained heavy use raises the room's temperature noticeably; a small, poorly ventilated room struggles in warm weather. |
Try it yourself · Activity 04
10 minBuild your own power and cooling checklist
Apply this to a machine you own or are planning.
- Find your GPU's manufacturer-published minimum PSU wattage, or the top card you are considering.
- Add a realistic estimate for your CPU and the rest of the system, then add genuine headroom on top of that total.
- Check your case's specification for maximum supported GPU length against the card's actual length.
- Look at the room the machine will live in and honestly assess ventilation and noise tolerance.
Did any single item on this checklist change your plan more than the GPU choice itself did?
Worked answer
Example: a build planned around a GPU whose manufacturer-published minimum was comfortably within an existing PSU's rated wattage, until the CPU, three drives and case fans were added up, at which point the existing PSU no longer had genuine headroom and needed replacing before the GPU could be fitted safely.
Learn in your browser · Chapter 05 of 07
The heavier case: what AI video generation actually demands
Local AI video generation is not just a bigger version of running a text model. It is a different, heavier problem, and the earlier chapters' numbers need revising upward before you buy anything with video in mind.
A text model processes one stream of tokens. A video generation model has to hold and process many frames at once, each a detailed image, across time as well as space, which is why open video-generation tools are typically far more demanding of VRAM than a text model of a similar-sounding size. Doubling a clip's length or resolution does not add a small amount of extra memory; it can push a job from comfortable to impossible on the same card.
Local video-generation tooling, as of this workbook's review, is overwhelmingly built and tested on NVIDIA's CUDA platform first. If AMD or Apple support for your chosen tool exists at all, check its own current documentation before buying hardware around it specifically, since this is one of the fastest-moving details in local AI and worth verifying fresh rather than assuming it matches the text-model situation in Chapter 2.
Once VRAM needs move into the tens of gigabytes, two honest routes open up. A single workstation-class or professional-tier GPU offers a large amount of VRAM in one card, at a real premium over consumer pricing. Running two or more consumer GPUs together, pooling their VRAM for a supported workload, is the other route some hobbyists take, and it asks more of your PSU, case, cooling and the software's own multi-GPU support than a single-card build does. Neither route is wrong; it depends on budget, build experience and patience with the extra setup work.
Try it yourself · Activity 05
10 minDecide if video generation changes your GPU choice
Revisit your Chapter 2 answer, now specifically for video.
- Write down the clip length and resolution you actually want to generate, honestly, not the maximum a tool advertises.
- Check your chosen video-generation tool's own current documentation for its stated VRAM guidance at that length and resolution.
- Compare that figure against the GPU you picked in Chapter 2, and note honestly whether it still holds up.
- If it does not, decide whether a bigger single card, a workstation-class card, or accepting shorter or lower-resolution clips is the better fit for your budget.
Did this chapter change your GPU choice, or confirm that video generation was never really your use case?
Worked answer
Example: someone who picked a 16 gigabyte consumer card in Chapter 2 for general text use, planning to also try video generation, checked their chosen tool's documentation and found even short clips at a moderate resolution were tight on 16 gigabytes. They revised the plan to either a 24 gigabyte card or accepting shorter, lower-resolution test clips on the card they already had.
Learn in your browser · Chapter 06 of 07
Buying practically: new, used and budget tiers
Put the last four chapters together and a real purchase decision, not just a set of specifications, should now be within reach.
Three honest tiers cover most people, without pinning this workbook to prices that will date almost immediately. An entry tier suits everyday local text and image use: a modest, often previous-generation GPU in the lower VRAM range from Chapter 2's table, in whatever shape suits how you actually work. A mid tier suits someone who wants headroom for larger local models or occasional light video generation: a recent mid-range GPU with more VRAM, usually in a desktop for the cooling and upgrade room. A serious tier suits committed video-generation work or several demanding tools at once: a high-VRAM flagship, a workstation-class card, or more than one GPU together, almost always a desktop or dedicated server rather than a laptop.
If Chapter 1 pointed you towards a home server rather than a desktop or laptop, self-hosting platforms such as Proxmox, TrueNAS or Unraid let you run a model, an agent or several separate services on one always-on machine, with the GPU passed through to whichever one needs it. This is genuinely useful, general-purpose infrastructure, not something built specifically for AI, and it is worth exploring on its own terms rather than assuming it is required just because you have chosen the server shape.
Scroll sideways to see every column.
| Tier | Rough fit | Shape that usually suits it |
|---|---|---|
| Entry | Everyday local text and image models | Laptop, desktop or a small always-on server |
| Mid | Larger local models, light or occasional video generation | Usually a desktop, for cooling and upgrade room |
| Serious | Committed video generation, or several demanding tools at once | Desktop or dedicated server, rarely a laptop |
Try it yourself · Activity 06
15 minDraft your own shopping list
Bring together every earlier chapter into one real list.
- State your tier honestly, from the table above, based on your actual planned use, not the most ambitious version of it.
- Name the specific GPU, or a short list of two or three candidates, checking current VRAM and manufacturer-published PSU guidance for each.
- Note the shape, laptop, desktop or server, and, if a server, whether you already know which self-hosting platform you would use.
- List the PSU, case and cooling checks from Chapter 3 against this specific GPU, not a generic assumption.
Looking at the finished list, is anything on it there because it seemed impressive rather than because your own use case in Chapter 1 actually needs it?
Worked answer
Example list, mid tier, desktop: a recent mid-range GPU with headroom above the entry tier's VRAM figure, a PSU sized to that card's manufacturer-published minimum plus genuine headroom for the rest of the system, a case confirmed to fit the card's physical length, and a decision to revisit the serious tier later only if video generation becomes a real, repeated need rather than a one-off experiment.
Learn in your browser · Chapter 07 of 07
What you can do now
A real hardware decision, not just a list of specifications, matched to how you actually plan to use it.
You can now explain why VRAM, not raw processor speed, decides what runs on a given machine, choose honestly between a laptop, a desktop workstation and a home server for your own situation, size a GPU against real VRAM tiers for both everyday local AI and the heavier case of AI video generation, and plan the PSU, cooling and case choices that actually make a GPU purchase work in practice.
https://trust-agent.ai/exam/workstation-or-home-server-for-aiThis is free educational content published by Mickai LTD, not professional or technical advice for your specific purchase, and Mickai accepts no liability for how you use it. Always check a component's own current specification sheet before buying.
Being able to say plainly what hardware your AI actually runs on, and who can reach it, is the same principle behind Mickai's approach to trustworthy AI: a human stays in control of the infrastructure, not just the model.
If you are reading this because your organisation is planning several of these machines rather than one, not just a single home workstation, Mickai builds bespoke AI workflows and code enhancements for businesses, running on Mickai's own sovereign operating system with zero data egress: your data and code never leave your own environment. See what that looks like at mickai.co.uk/bespoke.
Keep learning
The complete workbook
This workbook is the practical hardware companion to Trust Agent's software-focused local AI workbooks: what GPU, memory, power supply and case you actually need, and roughly which budget tier fits your use case. It covers the real trade-off between a laptop, a desktop workstation and an always-on home server, and treats AI video generation as the genuinely heavier case it is, with its own higher VRAM guidance. Every recommendation is framed as a tier or a principle rather than a fixed price, since exact costs date quickly.
- 01The one number that matters most: VRAMRead here · 1 exercise
Before any purchase, it helps to know which single specification actually predicts whether AI runs well on a machine, and it is not the one most people check first.
- 02Workstation, laptop or server: choosing the right shapeRead here · 1 exercise
The same GPU can go into three very different kinds of machine, and the right shape depends on how and where you will actually use it, not just the specification sheet.
- 03The GPU decision: what actually mattersRead here · 1 exercise
Once you know the shape of machine you want, the GPU inside it is the single highest-leverage choice you will make, and VRAM is still the first number to look at.
- 04Power, PSU and the rest of the buildRead here · 1 exercise
A powerful GPU is only as good as the power, cooling and case around it, and this is where people who priced the GPU carefully still get caught out.
- 05The heavier case: what AI video generation actually demandsRead here · 1 exercise
Local AI video generation is not just a bigger version of running a text model. It is a different, heavier problem, and the earlier chapters' numbers need revising upward before you buy anything with video in mind.
- 06Buying practically: new, used and budget tiersRead here · 1 exercise
Put the last four chapters together and a real purchase decision, not just a set of specifications, should now be within reach.
- 07What you can do nowRead here · Reading
A real hardware decision, not just a list of specifications, matched to how you actually plan to use it.
Also inside: a 8-point checklist, a glossary of 12 terms and 11 questions and answers to test yourself. 6 hands-on exercises, each with a worked answer at the back where the workbook gives one.
The PDF is free. We ask for your name and email before downloading. Read the privacy notice at the download form. Free to download and use for personal learning, study groups and inside your own team. Please do not resell the workbooks or republish them as your own. Link people to trust-agent.ai instead.
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Test yourself
Questions and answers
Why does VRAM matter more than processor speed for running AI locally?
A model's weights, and the extra memory it needs while working, have to fit in fast memory before anything else about the machine matters. If the model does not fit, no amount of processor speed changes that, which is why VRAM is the first number worth checking, not the last.
What is unified memory, and why does it change the picture on a Mac?
Unified memory is a single pool shared between the CPU and GPU on Apple Silicon Macs, rather than a separate, usually smaller VRAM pool. A Mac with a large unified memory pool can sometimes run a bigger model than a laptop with a similarly sized separate VRAM pool, because the GPU can reach the whole pool.
What is the real trade-off of choosing a laptop over a desktop for local AI?
A laptop GPU of the same name as a desktop card usually runs at lower power and therefore lower performance, and a thin case limits how hard you can push it for a sustained job. You gain portability, and pay for it in sustained performance and cooling headroom.
When does a home server make more sense than a desktop workstation?
When you want a model, agent or household AI tool available around the clock, reachable from other devices, rather than tied to a machine you sit at. A home server trades single-job speed for always-on availability, and makes noise and running heat matter more, since it runs continuously.
Besides VRAM, what else should genuinely influence a GPU choice?
The generation or architecture, since a newer generation is usually more efficient per gigabyte, and the software ecosystem, since a card only helps if the AI tools you actually want to use support it well today, worth checking directly rather than assuming from the specification sheet.
Why might an older, higher-VRAM GPU beat a newer card with less memory?
For local AI, running out of memory is a hard stop, not a graceful slowdown. Memory capacity and raw processing speed are different numbers, and for whether a model runs at all, capacity usually matters more than generation.
How should you size a PSU for a new GPU?
Start from the GPU manufacturer's own published minimum system wattage for that specific card, treat it as a floor rather than a target, add a realistic estimate for the rest of the system under load, and leave genuine headroom above the total.
Why do the newest high-power GPU connectors need extra care?
They have had real, documented reports of overheating when a cable is not fully seated or is bent sharply near the connector. Push the connector fully in, avoid a tight bend at the plug, and prefer a native cable over stacked adapters where your hardware supports it.
Why does AI video generation need so much more VRAM than a text model?
A video model holds and processes many detailed frames at once, across time as well as space, rather than one stream of text tokens. Increasing clip length or resolution does not add a small amount of extra memory; it can push a job from comfortable to impossible on the same card.
What is a realistic practical VRAM floor for serious local AI video generation?
Most people doing more than very short, low-resolution test clips find 24 gigabytes a realistic floor, with heavier, longer or higher-resolution work often planned around 32 to 48 gigabytes or more, on a single workstation-class card or, for the most demanding setups, several GPUs together.
What should you actually check before buying a used GPU?
Ask directly about its history, including whether it was used for cryptocurrency mining, check for physical damage, listen for fan noise on a test run if you can, and confirm whether any warranty actually transfers to you before paying.
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Key terms
- VRAM
- The dedicated memory built into a graphics card. Fast, and usually the smallest, most limiting memory pool for running an AI model on a GPU.
- System RAM
- The computer's main memory, shared with everything else it is doing. A model can run from system RAM on the CPU alone, but this is generally much slower than running on a GPU.
- Unified memory
- A single memory pool shared between the CPU and GPU, used by Apple Silicon Macs, which lets the GPU reach a larger amount of memory than a typical separate VRAM pool of the same size.
- GPU
- Graphics processing unit. The component that actually runs most AI model calculations, thanks to hardware built for the same kind of parallel arithmetic AI models need.
- PSU
- Power supply unit. Converts mains electricity into the power a computer's components use, with a maximum wattage it can safely deliver.
- Headroom
- Extra capacity kept above the minimum a component needs, in power supply wattage or memory, so the system is not running at its absolute limit during normal use.
6 of the workbook's 12 terms. The complete glossary is in the workbook.
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Created by Mickarle Wagstaff-Irons - Micky Irons with the Mickai team. Published by Mickai LTD. Last updated 29 September 2026.
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