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HomeCan I run it?Qwen3-14BQwen3-14B on an RTX 4090

Yes. Qwen3-14B at Q8_0 needs about 19.0 GB, and the GeForce RTX 4090 has 24.0 GB usable at a ~4k context.

Can I run Qwen3-14B on an RTX 4090?

Qwen3-14B at Q8_0 needs about 19.0 GB, and the GeForce RTX 4090 has 24.0 GB usable. That figure is 24 GB of VRAM on the spec sheet, of which 24.0 GB is usable for weights and cache, at 1008 GB/s memory bandwidth. Alibaba’s 14B Qwen3. It sits in the sweet spot for 12–16 GB cards that want more quality than an 8B. These are estimates from our formula, not measured benchmarks.

Quant that fits
Q8_0 Fits with headroom
Memory needed
19.0 GB at Q8_0, ~4k context
Usable VRAM
24.0 GB of 24 GB VRAM
Est. tokens/sec
39–55 estimate

Qwen3-14B · GeForce RTX 4090 · Everything this machine runs · Q4 vs Q8 vs FP16

Memory at each quant

QuantNeed vs 24.0 GBVerdict
Q4_K_M11.3 GBQ4Fits
Q8_019.0 GBQ8Fits
FP1635.0 GBFP16Won’t fit

Estimated tokens per second

Estimate: 39–55 tokens/sec at Q8_0. This is a bandwidth-derived range, not a bench. Efficiency is a 60–85% GPU band from How we calculate.

Context headroom

At Q8_0, this machine has headroom out to about 32k tokens under our KV estimate. Longer chats need more memory for the cache. Figures assume an FP16 KV cache.

Context headroom for Qwen3-14B on an RTX 4090 at Q8_0
ContextKV cache (FP16)Total at Q8_0Verdict
4k0.7 GB19.0 GBFits
8k1.3 GB19.7 GBFits
16k2.7 GB21.1 GBFits
32k5.4 GB23.7 GBTight
64k10.7 GB29.1 GBWon’t fit
128k21.5 GB39.8 GBWon’t fit

From the model’s config. Try other sizes in the VRAM calculator or see the context length guide.

What to do instead

Other hardware for Qwen3-14B

Other models on an RTX 4090

Quick answers

Can I run Qwen3-14B on an RTX 4090?
Yes. Qwen3-14B at Q8_0 needs about 19.0 GB, and the GeForce RTX 4090 has 24.0 GB usable.
How much VRAM does Qwen3-14B need?
About 11.3 GB at Q4_K_M, 19.0 GB at Q8_0 and 35.0 GB at FP16, estimated for a ~4k context.
How fast is Qwen3-14B on an RTX 4090?
Our estimate is 39–55 tokens per second at Q8_0. It is not a measured benchmark.
What context length can I use?
At Q8_0, our KV estimate supports up to about 32k tokens before the cache pushes the total over usable memory.

New models, and what they need to run

One short email a week: fresh open models with their VRAM numbers, plus hardware worth watching.