Buying guide
The best GPUs for running AI models locally (2026)
Memory decides which models you can run, and memory bandwidth decides how fast they answer. These are the cards that give you the most of both for the money.
The short version
For most people, a used RTX 3090 is still the GPU to buy: 24GB at 936 GB/s for about $1,050, enough to run Qwen3.8 27B at ~34 tok/s (estimated). On a tighter budget, the RTX 5060 Ti 16GB (about $620 new) runs gpt-oss-20b and Qwen3.5 9B entirely on the card. The RTX 5090 is the fastest consumer card, but the 2026 memory shortage has pushed it to about $4,300.
Our picks
Best overall
RTX 309024GB · ~$1,050 used24GB at 936 GB/s for about $1,050 used, the best mix of memory, speed and price. It runs the strongest models that fit on one card, such as Qwen3.8 27B.
Best budget
RTX 5060 Ti 16GB16GB · ~$620The cheapest new 16GB CUDA card. It runs gpt-oss-20b and Qwen3.5 9B entirely in VRAM and draws only 180W.
Fastest consumer GPU
RTX 509032GB · ~$4,3001,792 GB/s and 32GB make it about twice as fast as a 3090 on the same models, for about four times the price.
Best for multi-GPU builds
R970032GB · ~$1,80032GB per card, a blower cooler and a 300W rating, so four fit in one workstation for 128GB of VRAM. Buy it for capacity, not speed.
Most memory on one card
RTX PRO 600096GB · ~$16,00096GB at RTX 5090 bandwidth runs gpt-oss-120b and Qwen3.5 122B-A10B entirely on one card, for about $16,000.
Best for 100B-class models
Ryzen AI Max+ 395128GB · ~$3,300Not a graphics card but a mini PC chip that shares 128GB with its GPU. It runs gpt-oss-120b at ~35 tok/s (estimated) for about $3,300.
We may earn a commission when you buy through links on this page. It never changes what we recommend. How we make money
In this article
- How we picked
- Best overall: a used RTX 3090
- Best budget: RTX 5060 Ti 16GB
- Fastest consumer GPU: RTX 5090
- Best for multi-GPU builds: Radeon AI PRO R9700
- Most memory on one card: RTX PRO 6000 Blackwell
- Best for 100B-class models: Ryzen AI Max+ 395
- Our picks compared
- How much VRAM do you need?
- New or used?
- What about two or more GPUs?
- What to avoid
If you want to run large language models on your own computer, the graphics card matters more than anything else in the box. Two numbers decide almost everything. The amount of memory sets the largest model you can load, and the speed of that memory sets how quickly the model writes. Buy the most VRAM you can afford first, then the most bandwidth, and only then look at the rest of the spec sheet.
That makes 24GB the sweet spot in 2026. The strongest open models that fit on one card, such as Qwen3.8 27B and Gemma 4 31B, need about 18GB to 23GB at 4-bit, and the cheapest fast way to get 24GB is still a used RTX 3090. Below that, 16GB cards handle models up to about 20B parameters. Above it, you are paying for speed or for 32GB to 96GB of memory, and prices climb steeply.
How we picked
We rank cards on memory first, because a model that doesn’t fit in VRAM either won’t run or spills into system RAM that is many times slower. Bandwidth comes second: generating each token means reading the model’s active weights from memory, so a card with twice the bandwidth writes roughly twice as fast. Then price, measured as cost per gigabyte of reasonably fast memory. Software support breaks ties. NVIDIA’s CUDA runs everything, AMD’s ROCm and Vulkan run most popular tools, and Intel’s stack works but needs more setup.
We have not lab-tested these cards. Speeds in this guide come from our estimate model, which predicts single-user generation speed from memory bandwidth and model size and is calibrated against published llama.cpp results. The methodology page explains how it works and where it can be wrong. Estimates carry a tilde (~) and assume a llama.cpp-style runtime, 8K of context and one user. They cover generation speed only, not how fast a card reads a long prompt. Measured results live on our benchmarks page.
We judged every card on the open models people actually run in October 2026. For dense models that means Qwen3.8 27B and Gemma 4 31B. For fast mixture-of-experts (MoE) models, which only read a small slice of their weights per token, we used Qwen3.6 35B-A3B and gpt-oss-20b. For the big ones, gpt-oss-120b and Qwen3.5 122B-A10B. The chart shows why bandwidth matters so much: the same model at the same quantization runs about twice as fast on an RTX 5090 as on an RTX 3090, and more than three times as fast on a 3090 as on a 128GB mini PC.
Generation speed
Qwen3.8 27B at Q4_K_M: bandwidth sets the pace
Estimated tokens per second, single user, higher is better.
RTX 5090
32GB · 1,792 GB/s
~80tok/s
RTX 4090
24GB · 1,008 GB/s
~47tok/s
RTX 3090
24GB · 936 GB/s
~39tok/s
RX 7900 XTX
24GB · 960 GB/s
~36tok/s
R9700
32GB · 640 GB/s
~24tok/s
M5 Max 128GB
128GB · 614 GB/s
~23tok/s
Arc Pro B70
32GB · 608 GB/s
~20tok/s
Arc Pro B60
24GB · 456 GB/s
~15tok/s
DGX Spark
128GB · 273 GB/s
~12tok/s
Ryzen AI Max+ 395
128GB · 256 GB/s
~11tok/s
Estimates from our speed model. Measured results are on the benchmarks page.
Best overall: a used RTX 3090
Best overall
24GB
GDDR6X · 936 GB/s
The default value pick for 24GB of CUDA memory and the backbone of most multi-GPU builds.
- Typical price
- ~$1,050 used
- Best model it runs
- Qwen3.8 27B
- Largest comfortable fit
- Qwen3.6 35B-A3B (Q3_K_M)
- +24GB at 936 GB/s for less than half the price of a used RTX 4090
- +NVLink support for dual-card setups
- +Huge community knowledge base for multi-GPU builds
- −Hot rear-mounted memory on many cards
- −350W with sharp transient power spikes
- −Used cards may have mining or heavy-use history
The RTX 3090 came out in 2020, and it is still the card we would buy first. It has 24GB of GDDR6X at 936 GB/s, within 8 percent of the RTX 4090’s bandwidth, and used cards sold for about $1,050 to $1,450 in October 2026. At about $44 per gigabyte, it is the cheapest way to get fast memory in a card that drops into a normal desktop and runs current CUDA releases. Buy it if you want the best models that fit on one card and you are comfortable buying used.
It runs Qwen3.8 27B at Q5_K_M (about 21GB) at ~34 tok/s, estimated, or at Q4_K_M with 64K of context in about 22GB. Gemma 4 31B fits at Q4_K_M (about 22.5GB) at ~33 tok/s, though only with a modest context of around 16K tokens. MoE models are much quicker: Gemma 4 26B A4B at Q5_K_M runs at ~109 tok/s and gpt-oss-20b at ~119 tok/s. With 64GB of system RAM holding the rest of the model, gpt-oss-120b runs at ~21 tok/s. The best models for the RTX 3090 page lists everything else.
The downsides come with age. Many cards spent years in mining rigs, the memory chips on the back of the board run hot and often need new thermal pads, and the 350W rating hides sharp power spikes, so don’t skimp on the power supply. Newer cards also accelerate FP8 and FP4 formats in hardware, which the 3090 can’t. That matters for some vLLM deployments and very little for llama.cpp’s GGUF files.
If you prefer AMD, the RX 7900 XTX sells for about the same $1,050 used with 24GB at 960 GB/s, but prompt processing is slower and some tools are CUDA-only (RTX 3090 vs RX 7900 XTX). The RTX 4090 is nearly 20 percent faster at generation (~40 tok/s on Qwen3.8 27B at Q5_K_M, estimated) and much faster at reading long prompts, but used cards cost about $2,500 (RTX 3090 vs RTX 4090). If you won’t buy used, the RTX 5070 Ti costs about $1,200 new with 896 GB/s, but only 16GB (RTX 3090 vs RTX 5070 Ti). Our RTX 3090 guide covers buying and setting one up, and the Sleeper 3090 shows a complete single-card build.
Best budget: RTX 5060 Ti 16GB
Best budget
16GB
GDDR7 · 448 GB/s
The cheapest new way to get 16GB of CUDA memory, and a strong first LLM card.
- Typical price
- ~$620
- Best model it runs
- Qwen3.8 27B
- Largest comfortable fit
- Phi-4 (Q5_K_M)
- +16GB of VRAM at the lowest new price for NVIDIA
- +448 GB/s GDDR7 is a big step up from the RTX 4060 Ti
- +180W board power works with modest power supplies
- −128-bit bus limits speed on larger models
- −PCIe x8 link slows down on PCIe 3.0 systems
- −Easy to confuse with the 8GB version
The RTX 5060 Ti 16GB is the cheapest new card we’d buy for local AI. About $620 gets you 16GB of GDDR7 at 448 GB/s, full CUDA support and a 180W board power that works with modest power supplies. It’s the card for adding local AI to a gaming PC or building a first rig on a budget.
Sixteen gigabytes covers models up to about 20B parameters. gpt-oss-20b fits entirely on the card (about 15GB) and runs at ~74 tok/s, estimated, and Qwen3.5 9B runs at practically lossless Q8_0 at ~32 tok/s. MoE models hold up well when they spill over: Qwen3.6 35B-A3B at Q4_K_M runs at ~42 tok/s with part of it in system RAM. Dense 27B to 31B models are the limit. Qwen3.8 27B squeezes in only at Q3_K_M (about 15GB), with little room left for context.
The weak spot is the 128-bit memory bus, which leaves it roughly 40 percent slower than a 3090 on models both cards can hold. It also uses a PCIe 5.0 x8 link, which matters little for one card but can slow a two-card setup on an older PCIe 3.0 motherboard. Check that the listing says 16GB, because an 8GB card shares the name.
On a tighter budget, a used RTX 3060 12GB costs about $270 and runs Qwen3.5 9B at Q6_K at ~30 tok/s (RTX 3060 12GB vs RTX 5060 Ti 16GB). For about $650 new, the Intel Arc Pro B60 gives you 24GB, enough for Qwen3.8 27B at Q5_K_M, but its 456 GB/s bus and less mature software hold it to ~13 tok/s on that model (RTX 3090 vs Arc Pro B60). The RX 9060 XT 16GB costs about $470 but has nearly 30 percent less bandwidth (RTX 5060 Ti vs RX 9060 XT), and a used RTX 4060 Ti 16GB at about $380 is slower still (RTX 4060 Ti vs RTX 5060 Ti). If you can stretch to about $1,200, the RTX 5070 Ti doubles the bandwidth and runs gpt-oss-20b at ~125 tok/s. Two 5060 Tis make a 32GB pair for about $1,240, and the GPUter build shows a complete single-card system.
Fastest consumer GPU: RTX 5090
Fastest consumer GPU
32GB
GDDR7 · 1,792 GB/s
The fastest consumer card for local LLMs, but shortage pricing has more than doubled its cost.
- Typical price
- ~$4,300
- Best model it runs
- Qwen3.8 27B
- Largest comfortable fit
- Qwen3.6 35B-A3B (Q5_K_M)
- +Highest memory bandwidth of any consumer GPU at 1,792 GB/s
- +32GB fits 32B-class models at high quality with long context
- +Full CUDA support across llama.cpp, vLLM, ExLlamaV2 and SGLang
- −Street prices above $4,300 new in October 2026
- −575W board power needs a large PSU and strong cooling
- −Still too small for 70B dense models without offload
The RTX 5090 is the fastest card you can put in a normal desktop. Its 1,792 GB/s of bandwidth is almost double a 3090’s, and its 32GB holds the best single-card models at higher quality with room for long context. Buy it if speed is worth more to you than money, for example for coding agents that generate thousands of tokens per task.
Estimated, it runs Qwen3.8 27B at Q6_K (about 24GB) at ~60 tok/s, or at Q4_K_M at ~80 tok/s, about twice the 3090’s ~39 tok/s. Gemma 4 31B runs at Q5_K_M at ~59 tok/s, and Qwen3.6 35B-A3B fits at Q5_K_M with room to spare and runs at ~196 tok/s.
The catch is price. Launch MSRP was $1,999; in October 2026 new cards listed for about $4,300 to $5,000 because of the GDDR7 shortage. It also draws up to 575W through a single 12V-2x6 connector, so plan on a quality 1,000W or larger power supply and good case airflow. And 32GB still isn’t enough for gpt-oss-120b. With the rest of the model in system RAM, it runs at ~25 tok/s, barely ahead of a 3090 doing the same (~21 tok/s), because the slow system memory sets the pace.
Two used 3090s cost about $2,100 for 48GB: more memory, but not more speed. The RTX 4090 at about $2,500 used sits in between (RTX 4090 vs RTX 5090, RTX 3090 vs RTX 5090). The RTX 5080 is not a cheaper route to the same thing, since it has only 16GB (RTX 5080 vs RTX 5090).
Best for multi-GPU builds: Radeon AI PRO R9700
Best for multi-GPU builds
32GB
GDDR6 · 640 GB/s
32GB for far less than NVIDIA workstation cards and built for stacking, but no faster per card than an RX 9070 XT.
- Typical price
- ~$1,800
- Best model it runs
- Qwen3.8 27B
- Largest comfortable fit
- Qwen3.6 35B-A3B (Q5_K_M)
- +32GB per card for less than NVIDIA workstation cards
- +Blower cooler for dense multi-GPU builds
- +Official ROCm support
- −640 GB/s is modest for a 32GB card
- −Street price well above the $1,299 MSRP
- −Some CUDA-only tools will not run
The Radeon AI PRO R9700 is the cheapest well-supported way to put a lot of new VRAM in one tower. Each card has 32GB at 640 GB/s, a blower cooler that exhausts out the back and a 300W rating, so four fit in a workstation case for 128GB. At about $1,800 each (up from a $1,299 MSRP), that’s about $56 per gigabyte, against about $134 for an RTX 5090.
One card runs Qwen3.6 35B-A3B at Q5_K_M at ~78 tok/s and Qwen3.8 27B at Q6_K at ~18 tok/s, estimated. Four cards hold gpt-oss-120b entirely in VRAM at ~37 tok/s and Qwen3.5 122B-A10B at Q6_K at ~20 tok/s.
Be clear about what you are buying: capacity, not speed. On dense models one R9700 is slower than a used 3090 (~24 vs ~39 tok/s on Qwen3.8 27B at Q4_K_M, estimated), and tools that only support CUDA won’t run. ROCm officially supports the card, and both llama.cpp and vLLM work on it, so the common local stack is covered. Plan on Linux, where ROCm support is most complete.
The Arc Pro B70 is the cheapest new 32GB card at about $1,300, with similar bandwidth (608 GB/s) but software that still needs more setup (R9700 vs Arc Pro B70). Four used 3090s give you 96GB for about $4,200 and run gpt-oss-120b faster (~56 tok/s), but they draw about 1,400W on their own and usually need risers or an open frame, like the FJÄLLBO build. If you want CUDA at 32GB, see RTX 5090 vs R9700.
Most memory on one card: RTX PRO 6000 Blackwell
Most memory on one card
96GB
GDDR7 ECC · 1,792 GB/s
The most memory on a single PCIe card at RTX 5090-class bandwidth, at a very steep price.
- Typical price
- ~$16,000
- Best model it runs
- Qwen3.8 27B
- Largest comfortable fit
- Qwen3.5 122B-A10B (Q4_K_M)
- +96GB on one card avoids multi-GPU complexity
- +1,792 GB/s matches the RTX 5090
- +300W Max-Q version fits four to a workstation
- −Around $16,000 in October 2026
- −The 600W Workstation Edition needs serious cooling
The RTX PRO 6000 Blackwell puts 96GB on one card at the same 1,792 GB/s as the RTX 5090. That is enough to run 100B-class models entirely in VRAM, without the splitting, risers and power planning that multi-GPU rigs need. It is a card for professionals and well-funded enthusiasts. At about $16,000 in October 2026, close to double its 2025 street price, one card costs more than a complete four-3090 workstation.
The speed difference is large. Estimated, gpt-oss-120b runs at ~172 tok/s, Qwen3.5 122B-A10B at Q4_K_M at ~105 tok/s and GLM-4.5-Air at Q5_K_M at ~80 tok/s. A 128GB mini PC manages ~35 tok/s on gpt-oss-120b. Two cards (192GB) can run DeepSeek V4 Flash at its native FP4, at an estimated ~72 tok/s.
NVIDIA sells three versions with the same memory: a 600W Workstation Edition, a 300W Max-Q blower card that stacks four to a tower (as in the a16z workstation), and a passively cooled Server Edition. If 72GB is enough, the RTX PRO 5000 Blackwell 72GB holds gpt-oss-120b for about $9,100, the most recent street price we found (RTX 5090 vs RTX PRO 6000).
Best for 100B-class models: Ryzen AI Max+ 395
Best for 100B-class models
128GB
LPDDR5X-8000 · 256 GB/s
The cheapest way to run 100B-class MoE models in one quiet box, though prices have climbed past $3,300.
- Typical price
- ~$3,300
- Best model it runs
- Qwen3.5 122B-A10B
- Largest comfortable fit
- Qwen3.5 122B-A10B (Q4_K_M)
- +Up to 96GB of GPU memory on Windows and about 120GB on Linux
- +Small, quiet systems with configurable 45 to 120W chip power
- +Strong for MoE models such as gpt-oss-120b
- −256 GB/s makes dense 70B models slow
- −Slower prompt processing than DGX Spark or NVIDIA GPUs
- −Prices have risen sharply
Sometimes the best GPU for local AI isn’t a graphics card. The Ryzen AI Max+ 395, sold in mini PCs and known as Strix Halo, shares up to 128GB of memory between its CPU and its integrated GPU. Windows lets the GPU use up to 96GB, and Linux about 120GB after a kernel setting change. That’s as much GPU memory as the $16,000 RTX PRO 6000, in a quiet box whose chip runs at 45 to 120W.
Bandwidth is only 256 GB/s, which suits MoE models that read a small slice of their weights per token. gpt-oss-120b runs at ~35 tok/s, estimated, and Qwen3.5 122B-A10B at Q4_K_M at ~18 tok/s. A 24GB card with 64GB of system RAM manages ~21 tok/s on gpt-oss-120b, so the mini PC wins on the big models before you even count noise and power.
Dense models are another story. Gemma 4 31B at Q4_K_M runs at ~10 tok/s here against ~33 tok/s on a 3090, and prompt processing is slower than on NVIDIA hardware, so long documents take a while to read in. 128GB systems sold for about $3,300 to $4,350 in October 2026, up from about $2,000 in 2025. Our guide to the best Macs and mini PCs for local LLMs compares it with the Mac Studio and NVIDIA’s DGX Spark (DGX Spark vs Ryzen AI Max+ 395).
Our picks compared
The table puts our picks next to the main alternatives. The 120B column shows where the lines fall for a big model: 16GB cards can’t hold gpt-oss-120b even with 64GB of system RAM, 24GB and 32GB cards run it with part of the model offloaded (amber), and only the 96GB card and the mini PC run it entirely in fast memory.
| GPU | 9B speed | 27B speed | 120B MoE speed | Price |
|---|---|---|---|---|
| RTX 309024GB · 936 GB/s | ~98tok/s | ~39tok/s | ~21tok/s | ~$1,050 usedCheck Amazon ↗ |
| RTX 5060 Ti 16GB16GB · 448 GB/s | ~55tok/s | ~10tok/s | Won't fit | ~$620Check Amazon ↗ |
| RTX 509032GB · 1,792 GB/s | ~190tok/s | ~80tok/s | ~25tok/s | ~$4,300Check Amazon ↗ |
| R970032GB · 640 GB/s | ~61tok/s | ~24tok/s | ~23tok/s | ~$1,800Check Amazon ↗ |
| RTX PRO 600096GB · 1,792 GB/s | ~190tok/s | ~80tok/s | ~170tok/s | ~$16,000Check Amazon ↗ |
| Ryzen AI Max+ 395128GB unified · 256 GB/s | ~30tok/s | ~11tok/s | ~35tok/s | ~$3,300Check Amazon ↗ |
| RTX 409024GB · 1,008 GB/s | ~115tok/s | ~47tok/s | ~21tok/s | ~$2,500 usedCheck Amazon ↗ |
| RX 7900 XTX24GB · 960 GB/s | ~88tok/s | ~36tok/s | ~20tok/s | ~$1,050 usedCheck Amazon ↗ |
| RTX 5070 Ti16GB · 896 GB/s | ~105tok/s | ~13tok/s | Won't fit | ~$1,200Check Amazon ↗ |
| Arc Pro B6024GB · 456 GB/s | ~38tok/s | ~15tok/s | ~18tok/s | ~$650Check Amazon ↗ |
| Arc Pro B7032GB · 608 GB/s | ~49tok/s | ~20tok/s | ~21tok/s | ~$1,300Check Amazon ↗ |
How much VRAM do you need?
A model needs memory for its weights, for the context cache that grows with every token in the conversation, and for some runtime overhead. At 4-bit (Q4_K_M) with 8K of context, this is roughly where each memory size lands:
| VRAM | What fits comfortably | Example |
|---|---|---|
| 8GB | Small models up to about 9B | Qwen3.5 9B at Q4_K_M, about 7GB |
| 12GB to 16GB | Models up to about 20B | gpt-oss-20b, about 15GB |
| 24GB | Dense 27B to 31B, MoE up to 35B | Qwen3.8 27B at Q4_K_M, about 18GB |
| 32GB | The same models at Q5 or Q6, or with long context | Qwen3.8 27B at Q6_K, about 24GB |
| 70GB and up | 100B-class MoE models | gpt-oss-120b, about 68GB |
| Model | Size | Q4_K_M | Q6_K | Q8_0 |
|---|---|---|---|---|
| Qwen3.5 9B | 9B | 7.2 GB | 9.5 GB | 12 GB |
| gpt-oss-20b | 20.9B (3.6B active) | 15 GBMXFP4 | — | — |
| Gemma 4 26B A4B | 26B (3.8B active) | 17 GB | 23 GB | 30 GB |
| Qwen3.8 27B | 27B | 18 GB | 25 GB | 32 GB |
| Gemma 4 31B | 31B | 22 GB | 30 GB | 36 GB |
| Qwen3.6 35B-A3B | 35B (3B active) | 24 GB | 32 GB | 41 GB |
| gpt-oss-120b | 117B (5.1B active) | 68 GBMXFP4 | — | — |
| Qwen3.5 122B-A10B | 122B (10B active) | 77 GB | 104 GB | 134 GB |
Context adds up. Qwen3.8 27B at Q4_K_M needs about 18GB at 8K tokens, about 22GB at 64K and about 26GB at 128K. Gemma 4 31B grows faster, from about 22.5GB at 8K to about 27GB at 64K. Quantization is the other lever: Q4_K_M keeps most of a model’s quality at about 30 percent of its 16-bit size, and Q8_0 is close to lossless at about half. Our guides to how much VRAM you need and quantization go deeper, and the VRAM calculator checks any model, quantization and context length against your card.
New or used?
Used is where the value is in 2026. The shortage hit new cards hardest, so a used RTX 3090 at about $1,050 gets you more memory than a new $1,200 RTX 5070 Ti. When you buy used, pick a seller or marketplace that accepts returns, and run a long generation job as soon as the card arrives while you watch temperatures. Hot memory or throttling usually points to tired thermal pads, which are a cheap fix, but you want to find out inside the return window.
Old datacenter cards are the other used route, and they ask more of you. The Tesla P40 is the cheapest 24GB card at about $230 to $330, but it has no tensor cores, very slow FP16, passive cooling that needs a fan shroud, and no support in CUDA 13 (RTX 3090 vs Tesla P40). The Tesla V100 32GB has 900 GB/s for about $700, but most units are SXM2 modules that need an adapter board and custom cooling, as in this V100 workstation, and CUDA 13 dropped it too. The Instinct MI50 32GB was a bargain at about $150 before the shortage; at $600 or more, and without support in current ROCm releases, it no longer is (RTX 3090 vs MI50).
Used workstation cards hold their value. A 48GB RTX A6000 sold for about $4,400 and an RTX 6000 Ada for $4,750 or more, which is RTX 5090 money for more memory but much less bandwidth.
What about two or more GPUs?
Adding cards adds memory, not speed. llama.cpp and the apps built on it split a model’s layers across GPUs, and each token passes through the cards one after another, so two cards run a model at about the speed of one. What you gain is room for bigger models and better quantizations. Estimated, two 3090s (48GB) run Qwen3.8 27B at Q8_0 at ~22 tok/s and cut gpt-oss-120b’s offloading enough to reach ~32 tok/s. Four (96GB) hold gpt-oss-120b entirely, at ~56 tok/s.
Tensor parallelism in vLLM and similar runtimes can make several cards faster than one, but it works best with matched cards and a fast link between them. The 3090 is one of the last GeForce cards with NVLink, which is why dual-3090 rigs such as the Hardigg 3090 still use it.
Plan the platform before you buy the cards. Most consumer motherboards have one full-speed x16 slot and at best split it into two x8 slots, so two GPUs is the practical limit. Three or more call for a workstation or server platform with more PCIe lanes (Threadripper, Xeon or EPYC), as in The Machine with twelve 3090s or PewDiePie’s seven-card RTX 4000 Ada rig. Size the power supply for the cards’ combined rating plus 20 to 30 percent headroom. If you are building a Linux server, our guide to NVIDIA GPUs on Linux covers drivers and setup.
What to avoid
8GB cards. The RTX 5060 costs about $450, and models like Qwen3.5 9B at Q4_K_M (about 7GB) are its ceiling. Spend about $170 more on the 16GB RTX 5060 Ti.
12GB cards at new-card prices. The RTX 5070 has fast memory (672 GB/s), but at about $800 for 12GB it costs more than the 16GB 5060 Ti and holds smaller models.
The RTX 5080 for AI alone. At about $1,600 it has the same 16GB as the RTX 5070 Ti and only about 7 percent more bandwidth.
A used RTX 4090 at full price. At $2,500 to $3,000 it costs more than twice as much as a 3090 for the same 24GB. It makes sense only if you need its faster prompt processing.
Old hardware at shortage prices. Pascal cards like the P40 have lost CUDA 13 support, and the MI50 has lost current ROCm support. They still run llama.cpp, but they are tinkerer’s cards, not safe buys.
Low-memory lookalikes. The RTX 5060 Ti, RTX 3060 and RX 9060 XT all come in 8GB versions with the same name. The 8GB RTX 3060 also has a narrower bus. Check the memory size before you pay.
Frequently asked questions
Is 16GB of VRAM enough for local LLMs?
Yes, for models up to about 20B parameters. A 16GB card holds gpt-oss-20b (about 15GB) or Qwen3.5 9B at Q8_0 (about 12GB) entirely in VRAM, and an RTX 5060 Ti 16GB runs gpt-oss-20b at about 74 tok/s (estimated). Dense 27B to 31B models such as Qwen3.8 27B need about 18GB to 23GB at 4-bit, so they call for a 24GB card or a 3-bit quantization with little room for context.
Is the RTX 3090 still worth buying for AI in 2026?
Yes. A used RTX 3090 has 24GB of VRAM at 936 GB/s and sold for about $1,050 to $1,450 in October 2026, the cheapest way to get fast 24GB memory with current CUDA support. It runs Qwen3.8 27B at Q5_K_M at about 34 tok/s (estimated). Expect a 350W card whose memory may need new thermal pads, and buy from a seller that accepts returns.
Is the RTX 5090 worth it for running LLMs?
Only if speed matters more to you than cost. The RTX 5090's 32GB and 1,792 GB/s make it about twice as fast as an RTX 3090, running Qwen3.8 27B at Q4_K_M at about 80 tok/s against about 39 tok/s (both estimates). It cost about $4,300 new in October 2026, more than double its $1,999 MSRP, while two used 3090s give you 48GB for about $2,100.
How much VRAM do I need to run gpt-oss-120b?
About 68GB with 8K of context at its native MXFP4 format. That fits on a single 96GB RTX PRO 6000 Blackwell (about 172 tok/s, estimated), a 72GB RTX PRO 5000, or a 128GB unified-memory system such as a Ryzen AI Max+ 395 mini PC (about 35 tok/s). A 24GB GPU with 64GB of system RAM can also run it by offloading part of the model, at about 21 tok/s.
Are AMD and Intel GPUs good for local LLMs?
Yes, with caveats. AMD's RX 7900 XTX and Radeon AI PRO R9700 run llama.cpp well through ROCm or Vulkan, and Intel's Arc Pro B60 and B70 offer 24GB and 32GB at low prices. AMD cards are slower at prompt processing than comparable NVIDIA cards, Intel's software needs more setup, and some tools only support CUDA. If you mainly use llama.cpp and apps built on it, they are reasonable choices.
Do two GPUs make an LLM run faster?
Not with the usual llama.cpp setup. Splitting a model across two GPUs adds their memory together, but it runs at about the speed of one card because each token passes through the cards in turn. Two RTX 3090s (48GB) let you run bigger models or higher-quality quantizations, and tensor-parallel runtimes such as vLLM can add speed with matched cards.
Go deeper
Hardware and models in this article
GDDR6X · 936 GB/s
RTX 3090
~$1,050 used
GDDR7 · 448 GB/s
RTX 5060 Ti 16GB
~$620
GDDR7 · 1,792 GB/s
RTX 5090
~$4,300
GDDR6 · 640 GB/s
R9700
~$1,800
GDDR7 ECC · 1,792 GB/s
RTX PRO 6000
~$16,000
LPDDR5X-8000 · 256 GB/s
Ryzen AI Max+ 395
~$3,300
GDDR6X · 1,008 GB/s
RTX 4090
~$2,500 used
GDDR6 · 960 GB/s
RX 7900 XTX
~$1,050 used
GDDR7 · 896 GB/s
RTX 5070 Ti
~$1,200
GDDR6 ECC · 608 GB/s
Arc Pro B70
~$1,300
Alibaba Qwen
Qwen3.8 27B
27B · 256K ctx
Gemma 4 31B
31B · 256K ctx
Alibaba Qwen
Qwen3.6 35B-A3B
35B (3B active) · 256K ctx
OpenAI
gpt-oss-20b
20.9B (3.6B active) · 128K ctx
OpenAI
gpt-oss-120b
117B (5.1B active) · 128K ctx
Alibaba Qwen
Qwen3.5 9B
9B · 256K ctx
Read next
More from Llama Builds
Buying guide
The best Macs and mini PCs for running LLMs locally (2026)
Unified-memory machines hold models that no affordable graphics card can, but their slower memory means you have to choose your models with care.
Updated Oct 14, 2026
Explainer
How much VRAM do you need to run LLMs locally?
Weights, KV cache and overhead, worked out with real numbers for the open models people actually run in 2026.
Updated Oct 14, 2026
Opinion
Is the RTX 3090 still the best GPU for local AI in 2026?
Six years after launch, it's still the card I tell most people to start with. Here's why, and where it stops being the right answer.
Updated Oct 14, 2026