Qwen3.5 397B A17B — Hardware Requirements & GPU Compatibility
Vision
Qwen3.5 397B A17B is a 403.4B-parameter open language model from Alibaba in the Qwen 3.5 family. It supports a context window of up to 262,144 tokens. At Q4_K_M it needs about 242.46 GB of VRAM — see which GPUs and Macs can run it below.
392.7K downloads
1.5K likesSpecifications
- Publisher
- Alibaba
- Family
- Qwen 3.5
- Parameters
- 403.4B
- Architecture
- Qwen3_5MoeForConditionalGeneration
- Context Length
- 262,144 tokens
- Vocabulary Size
- 248,320
- Release Date
- 2026-02-16
- License
- Apache 2.0
Get Started
HuggingFace
How Much VRAM Does Qwen3.5 397B A17B Need?
Select a quantization to see compatible GPUs below.
| Quantization | Bits | VRAM | + Context | File Size | Quality |
|---|---|---|---|---|---|
| Q2_Kest. | 3.40 | 171.9 GB | 187.8 GB | 171.44 GB | 2-bit quantization with K-quant improvements |
| Q3_K_Mest. | 3.90 | 197.1 GB | 213.1 GB | 196.66 GB | 3-bit medium quantization |
| Q4_K_Mest. | 4.80 | 242.5 GB | 258.4 GB | 242.04 GB | 4-bit medium quantization — most popular sweet spot |
| Q5_K_Mest. | 5.70 | 287.9 GB | 303.8 GB | 287.42 GB | 5-bit medium quantization — good quality/size tradeoff |
| Q6_Kest. | 6.60 | 333.2 GB | 349.2 GB | 332.80 GB | 6-bit quantization, very good quality |
| Q8_0est. | 8.00 | 403.8 GB | 419.8 GB | 403.40 GB | 8-bit quantization, near-lossless |
| BF16est. | 16.00 | 807.2 GB | 823.2 GB | 806.80 GB | Brain floating point 16 — preferred for training |
est.= calculated VRAM estimate; no published GGUF file found for that quantization yet. Other rows are verified against real community uploads.
Which GPUs Can Run Qwen3.5 397B A17B?
Q4_K_M · 242.5 GBQwen3.5 397B A17B (Q4_K_M) requires 242.5 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 316+ GB is recommended. Using the full 262K context window can add up to 16.0 GB, bringing total usage to 258.4 GB. No single GPU has enough memory — multi-GPU or cluster setups are needed.
Which Devices Can Run Qwen3.5 397B A17B?
Q4_K_M · 242.5 GB3 devices with unified memory can run Qwen3.5 397B A17B, including NVIDIA DGX H100, NVIDIA DGX A100 640GB.
Runs great
— Plenty of headroomWhere to Download Qwen3.5 397B A17B
Community quantizations of this model — GGUF for llama.cpp, Ollama, and LM Studio, plus AWQ/MLX variants where available.
Benchmarks
Benchmark details →Related Models
Frequently Asked Questions
- How much VRAM does Qwen3.5 397B A17B need?
Qwen3.5 397B A17B requires 242.5 GB of VRAM at Q4_K_M, or 807.2 GB at BF16. Full 262K context adds up to 16.0 GB (258.4 GB total).
VRAM = Weights + KV Cache + Overhead
Weights = 403.4B × 4.8 bits ÷ 8 = 242 GB
KV Cache + Overhead ≈ 0.5 GB (at 2K context + ~0.3 GB framework)
KV Cache + Overhead ≈ 16.4 GB (at full 262K context)
VRAM usage by quantization
Q4_K_M242.5 GBQ4_K_M + full context258.4 GB- Can NVIDIA GeForce RTX 5090 run Qwen3.5 397B A17B?
No — Qwen3.5 397B A17B requires at least 171.9 GB at Q2_K, which exceeds the NVIDIA GeForce RTX 5090's 32 GB of VRAM.
- What's the best quantization for Qwen3.5 397B A17B?
For Qwen3.5 397B A17B, Q4_K_M (242.5 GB) offers the best balance of quality and VRAM usage. Q5_K_M (287.9 GB) provides better quality if you have the VRAM. The smallest option is Q2_K at 171.9 GB.
VRAM requirement by quantization
Q2_K171.9 GBQ4_K_M ★242.5 GBQ5_K_M287.9 GBQ6_K333.2 GBQ8_0403.8 GBBF16807.2 GB★ Recommended — best balance of quality and VRAM usage.
- Can I run Qwen3.5 397B A17B on a Mac?
Qwen3.5 397B A17B requires at least 171.9 GB at Q2_K, which exceeds the unified memory of most consumer Macs. You would need a Mac Studio or Mac Pro with a high-memory configuration.
- Can I run Qwen3.5 397B A17B locally?
Yes — Qwen3.5 397B A17B can run locally on consumer hardware. At Q4_K_M quantization it needs 242.5 GB of VRAM. Popular tools include Ollama, LM Studio, and llama.cpp.
- How fast is Qwen3.5 397B A17B?
At Q4_K_M, Qwen3.5 397B A17B can reach ~18 tok/s on AMD Instinct MI350X. Speed depends mainly on GPU memory bandwidth. Real-world results typically within ±20%.
tok/s = (bandwidth GB/s ÷ model GB) × efficiency
Example: NVIDIA B300 → 8000 ÷ 242.5 × 0.65 = ~21 tok/s
Estimated speed at Q4_K_M (242.5 GB)
~21 tok/s~18 tok/s~18 tok/sReal-world results typically within ±20%. Speed depends on batch size, quantization kernel, and software stack.
- What's the download size of Qwen3.5 397B A17B?
At Q4_K_M, the download is about 242.04 GB. The full-precision BF16 version is 806.80 GB. The smallest option (Q2_K) is 171.44 GB.
- Which GPUs can run Qwen3.5 397B A17B?
No single consumer GPU has enough VRAM to run Qwen3.5 397B A17B at Q4_K_M (242.5 GB). Multi-GPU or professional hardware is required.
- Which devices can run Qwen3.5 397B A17B?
4 devices with unified memory can run Qwen3.5 397B A17B at Q4_K_M (242.5 GB), including Mac Studio (M3 Ultra, 256GB), Mac Studio (M3 Ultra, 512GB), NVIDIA DGX A100 640GB, NVIDIA DGX H100. Apple Silicon Macs use unified memory shared between CPU and GPU, making them well-suited for local LLM inference.