By amount of VRAM

What can you run with 24 GB of VRAM? 30B models, long context and the 70B question

24 GB is the amount most people mean when they say a card is good for local AI. It holds the 27B to 32B class of dense models at a quality that is hard to tell from the full-precision version in daily use, it leaves a real context window, and it runs the fast mixture-of-experts models with room to spare. It is also where the next question starts, which is whether the 70B models are within reach. They are, with caveats.

What fits

Usable memory is about 23.2 GB. That takes a 27B model at Q6, a 32B at Q4_K_M, or a 24B at Q8, and still leaves room for a window of 16k or more. The strongest pairings the engine finds on an RTX 3090 are below.

PickModelDownloadMemorySpeed
Best all-rounder Qwen3.5 27B Q6_K 21.3 GB 33 t/s
Best for code Qwen3 32B Q4_K_M 20.4 GB 34.5 t/s
Best for reasoning Qwen3.5 27B Q6_K 21.3 GB 33 t/s
Largest that still runs well Mixtral 8x7B Instruct V0.1 Q3_K_M 22.6 GB 58.3 t/s
Estimated on the GeForce RTX 3090 (24 GB, 936 GB/s) at an 8k context window.
ModelParametersDownloadMemorySpeedLongest context
Qwen3.5 27B 27.78B Q6_K 21.3 GB 33 t/s 32k
Gemma 4 31B Instruct 31.27B Q4_K_M 21.3 GB 33 t/s 8k
Qwen3 32B 32.76B Q4_K_M 20.4 GB 34.5 t/s 16k
Granite 4.1 30B 28.87B Q5_K_M 21.5 GB 32.6 t/s 8k
Gemma 3 27B Instruct 27.43B Q6_K 22.5 GB 31.3 t/s 16k
Qwen2.5 32B Instruct 32.76B Q4_K_M 20.4 GB 34.5 t/s 16k
Gemma 4 26B A4B Instruct 25.81B (3.74B active) Q6_K 20.9 GB 108.6 t/s 32k
Qwen2.5 Coder 32B Instruct 32.76B Q4_K_M 20.4 GB 34.5 t/s 16k
GLM 4.7 Flash 31.22B (3.66B active) Q5_K_M 21.2 GB 142 t/s 32k
Gemma 4 12B Instruct 11.96B Q8_0 13.6 GB 52.4 t/s 64k
Mistral Small 24B Instruct 2501 23.57B Q6_K 19.2 GB 36.8 t/s 32k
Qwen3 14B 14.77B Q8_0 15.5 GB 45.6 t/s 32k
The strongest pairings that fit entirely in memory, best first.

Choosing between a 27B at Q6 and a 32B at Q4 is a matter of taste and workload. The 32B has more parameters and a lower-quality quantization, and the 27B is smaller and closer to lossless. For code and reasoning we lean to the 32B. For chat and writing, the difference is small enough that the 27B's extra headroom for context decides it.

The mixture-of-experts models change the experience more than any of the dense ones. GLM 4.7 Flash generates at about 142 tokens per second on this card, and gpt-oss-20b fits whole with a long window and answers at about 167. Against roughly 34.5 for a dense 32B, that is a change you feel in every response. We would keep one of each installed: a dense model for the hard questions and a MoE for everything else.

Context at this size

At 24 GB the cache starts to matter, because the weights already take most of the card. Here is a 32B model at Q4_K_M as the window grows:

ContextKV cacheTotal memory
4k 1.00 GB 19.4 GB
8k 2.00 GB 20.4 GB
16k 4.00 GB 22.4 GB
32k 8.00 GB 26.4 GB
Qwen3 32B at Q4_K_M, F16 cache.

On a 24 GB card the 32B at Q4_K_M reaches about 16k before it runs out, and a 27B at Q6 reaches about 32k, since its attention design keeps the cache small. If you need very long windows, the choice of model decides it. A hybrid-attention model gets you to 64k or more where a classic 32B stops at 16k.

The 70B question

A 70B model at Q4_K_M needs about 42.1 GB, which is nearly twice what the card holds. With the rest in system RAM, our engine estimates about 1.5 tokens per second on an RTX 3090 with 64 GB of RAM. That is a number you can use for an occasional hard question and not for a conversation. At 2 bits it fits, and the quality loss at that precision on a model this size is something we would not recommend.

The realistic ways to run a 70B are two 24 GB cards, which is 48 GB and holds it at 4 bits, or a Mac with 64 GB or more of unified memory. Our multi-GPU guide covers the first, and the Mac and PC comparison the second. For a single 24 GB card, the better question is whether a very good 32B does the job, and for most work it does.

Which cards have 24 GB

DeviceMemoryBandwidthPrice
GeForce RTX 4090
Desktop GPU
24 GB 1008 GB/s $1,900
GeForce RTX 3090 Ti
Desktop GPU, used
24 GB 1008 GB/s $800
Radeon RX 7900 XTX
Desktop GPU
24 GB 960 GB/s $850
GeForce RTX 3090
Desktop GPU, used
24 GB 936 GB/s $700
GeForce RTX 5090 Laptop
Laptop GPU
24 GB 896 GB/s n/a
RTX A5000
Workstation GPU, used
24 GB 768 GB/s $1,200
Apple M4 Pro 24GB
Unified memory
24 GB 273 GB/s $1,399
Apple M5 24GB
Unified memory
24 GB 153 GB/s $1,799
Ryzen AI 9 HX 370 24GB
Unified memory
24 GB 128 GB/s n/a
Apple M4 24GB
Unified memory
24 GB 120 GB/s $799
Sorted by memory bandwidth, which sets generation speed. Prices are indicative.

The RTX 3090 and 3090 Ti, the RTX 4090, the RX 7900 XTX and the workstation RTX A5000 all have 24 GB. Compared on the same models:

Device Memory Bandwidth Qwen3 32BQwen3.5 27BGPT OSS 20B
GeForce RTX 3090 24 GB 936 GB/s 34.5 t/s44.3 t/s168 t/s
GeForce RTX 3090 Ti 24 GB 1008 GB/s 37.1 t/s47.7 t/s181 t/s
GeForce RTX 4090 24 GB 1008 GB/s 37.1 t/s47.7 t/s181 t/s
Radeon RX 7900 XTX 24 GB 960 GB/s 30.0 t/s38.5 t/s146 t/s
RTX A5000 24 GB 768 GB/s 28.3 t/s36.3 t/s138 t/s
Single-stream generation at Q4_K_M and an 8k window, from the same engine as the calculator.

The 4090's lead over a 3090 on generation is under 10%, because memory bandwidth went from 936 to 1008 GB/s and bandwidth is what sets the speed. The 4090 is far faster at reading a long prompt and at image generation, where compute matters. For chat with a local model, a used 3090 at a third of the price is the sensible purchase, as our used GPU guide explains.

Our advice at this tier

Install a dense model in the 27B to 32B range and a fast MoE, set the window to what you use, and leave a gigabyte free. If you want the 70B class, plan for 48 GB and not for squeezing it onto one card. And if you are still deciding whether to buy, 24 GB is the point where the extra money stops buying capability you will miss and starts buying capability you will not.

Questions people ask

What is the best LLM for 24 GB of VRAM?

Qwen3.5 27B at Q6_K or a 32B model such as Qwen3 32B at Q4_K_M are the strongest dense choices, and a mixture-of-experts model such as GLM 4.7 Flash or gpt-oss-20b is the pick when you want speed and a long window.

Can I run a 70B model on 24 GB of VRAM?

Not well. A 70B at 4 bits is around 42 GB, so about half of it lives in system RAM and it generates at a few tokens per second. Two 24 GB cards, or a Mac with 64 GB or more, are the realistic ways to run one.

Is the RTX 3090 or the RTX 4090 better for local LLMs?

The 4090 is faster, but only by about 8% on generation, because its memory bandwidth is only slightly higher. For local models the used 3090 gives nearly the same experience for about a third of the price.

How long a context can 24 GB handle?

With a 27B to 32B model at 4 bits, 16k to 32k. With a smaller model or a hybrid-attention model, 64k and more, since the weights leave more room for the cache.

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