Qwen3.6 35B-A3B on H200 141GB SXM (141GB) — VRAM, KV Cache & Throughput

Qwen3.6 35B-A3B (35.95B total, 3B active, Hybrid Linear/Mamba + MoE) uses 20.82 GiB of 4-bit weights (UD-Q4_K_XL), requiring 21.6 GiB total at 8K context and 22.07 GiB at 32K on H200 141GB SXM (~336.5 tok/s decode).

Interactive Sizing Workbench

Full Compatibility Report →
141 GB · 4800 GB/s
Fits with Safe Headroom
Measured GGUF shard size HF config.json ↗
Memory Allocation Breakdown (GiB) 21.6 GiB (23.19 GB) / 141 GiB (15%)
Model Weights: 20.82 GiB KV Cache & State: 0.22 GiB Runtime & Activation Buffers: 0.56 GiB System RAM Offload: 0 GiB
Required GPU Memory
21.6 GiB
23.19 GB (decimal)
Usable Hardware Memory
133.9 GiB
141 GB (physical)
Safe Headroom
+112.3 GiB
15% utilization
Est. Decode Throughput
~336.5 tok/s
3B active params
Est. Prefill Throughput
~24000 tok/s
4K Prompt TTFT: ~171 ms
Est. Cost / 1M Tokens
$0.16
Hybrid Linear/Mamba + MoE · Apache-2.0

Recommended Hardware for Current Configuration

Best Single GPU
Arc Pro B60 24GB (24GB)
~$599
Best Value / Used GPU
RTX 3090 (24GB)
~$750
Apple Unified Memory
Ryzen AI Max+ 395 128GB
~$1,999
Cloud From
Vast.ai · $0.19 / hr
1x RTX 3090

Production Launch Commands

llama.cpp (GGUF)
llama-server -hf unsloth/Qwen3.6-35B-A3B-GGUF:UD-Q4_K_XL \
  --ctx-size 8192 -ngl 999 --flash-attn
vLLM
vllm serve Qwen/Qwen3.6-35B-A3B \
  --max-model-len 8192 --gpu-memory-utilization 0.92
Live Token Speed Simulator (TTFT ~171ms · ~336.5 tok/s)
[Qwen3.6 35B-A3B · 21.6 GiB] allocated on target GPU. Prefill completed in TTFT window; streaming autoregressive tokens at memory-bandwidth-bound rate...

Cloud GPU Comparison & Rent-vs-Buy TCO

Verified public rates across RunPod, Vast.ai, Vultr, and DigitalOcean.

Verified: 2026-11-04
Purchase break-even
~26.6 months
Est. local power: $4.26 / mo
Provider Recommended Instance Total VRAM Hourly Rate Monthly at Selected Hours Billing Mode Deploy
RunPod 1x RTX 3090 (Community Cloud) 24 GB $0.22 / hr $26.75 / mo Per-second Deploy GPU ↗
Vast.ai 1x RTX 3090 (Verified Host) 24 GB $0.19 / hr $22.98 / mo Spot / On-demand Deploy GPU ↗
Vultr ($300 Free Credit*) 1x L40S 48GB (Dedicated Instance · $300 Credit*) 48 GB $1.67 / hr $203.19 / mo Hourly Deploy GPU ↗
Vultr Cloud GPU 1x L40S 48GB (Dedicated Instance) 48 GB $1.67 / hr $203.19 / mo Hourly Deploy GPU ↗
DigitalOcean 1x RTX 6000 Ada (Dedicated Instance) 48 GB $1.57 / hr $190.91 / mo Per-second Deploy GPU ↗

Rates reflect public listings on the verification date and fluctuate with regional inventory.

Fine-Tuning VRAM Requirements (QLoRA / LoRA / Full) — Qwen3.6 35B-A3B

QLoRA (4b) Fits with Safe Headroom
23.03 GiB
Model Weights: 20.82 GiB · Gradients + Optimizer: 1.2 GiB · Act: 1.01 GiB
Recommended GPU: Radeon AI PRO R9700 32GB (32GB)
LoRA (16b) Fits with Safe Headroom
70.1 GiB
Model Weights: 66.96 GiB · Gradients + Optimizer: 1.8 GiB · Act: 1.34 GiB
Recommended GPU: RTX PRO 6000 Blackwell (96GB)
Full BF16 Exceeds Available GPU Memory
276.9 GiB
Model Weights: 66.96 GiB · Gradients + Optimizer: 207.58 GiB · Act: 2.36 GiB
Recommended GPU: 2x B200 180GB (360GB)

Engineering Sizing Notes & Optimization Playbook

Quick Hardware Verdict

H200 141GB SXM (141GB physical, 133.9 GiB usable) runs 4-bit (UD-Q4_K_XL) Qwen3.6 35B-A3B at 8K context using 21.6 GiB with 112.3 GiB of safe headroom (~336.5 tok/s single-stream decode).

KV Cache & Runtime Tuning

Qwen3.6 35B-A3B uses Hybrid Linear/Mamba + MoE (35.95B total, 3B active per token). Moving from 8K to 32K context expands FP16 KV cache from 0.22 GiB to 0.69 GiB; enabling 8-bit KV cache (llama.cpp -ctk q8_0 -ctv q8_0 or vLLM --kv-cache-dtype fp8) saves 0.32 GiB at 32K (reducing total VRAM to 21.75 GiB).

VRAM Scaling Across Context Windows (4K to 128K, 4-bit Weights)

Qwen3.6 35B-A3B VRAM scaling from 4K to 128K context (4K: 21.51 GiB, 8K: 21.6 GiB, 32K: 22.07 GiB, 128K: 23.94 GiB) 4K 21.51 GiB (KV 0.14 GiB) 8K 21.6 GiB (KV 0.22 GiB) 32K 22.07 GiB (KV 0.69 GiB) 128K 23.94 GiB (KV 2.56 GiB) H200 141GB SXM (141GB)
Model weights remain constant while attention KV cache grows with context length and batch size.

Quantization Precision & Memory Matrix — Qwen3.6 35B-A3B @ 8K

Quantization Format Weights (GiB) KV Cache Total VRAM (GiB) Decode Speed Compatibility (H200 141GB SXM) Recommended GPU Data Source
Native Weights (BF16 / FP8 / MXFP4 — Lossless) (BF16) 66.96 GiB 0.22 GiB 67.74 GiB (72.74 GB) ~215.9 tok/s Fits with Safe Headroom RTX PRO 6000 Blackwell (96GB) Official checkpoint size
FP8 / GGUF Q8_0 (8-bit — Near-Lossless) (Q8_0) 34.37 GiB 0.22 GiB 35.15 GiB (37.74 GB) ~289.1 tok/s Fits with Safe Headroom A40 48GB (48GB) Measured GGUF shard size
GGUF Q6_K (6-bit — High Precision) (Q6_K) 27.3 GiB 0.22 GiB 28.08 GiB (30.15 GB) ~312 tok/s Fits with Safe Headroom Radeon AI PRO R9700 32GB (32GB) Measured GGUF shard size
GGUF Q5_K_M (5-bit — Balanced) (Q5_K_M) 24.64 GiB 0.22 GiB 25.42 GiB (27.29 GB) ~321.6 tok/s Fits with Safe Headroom Radeon AI PRO R9700 32GB (32GB) Measured GGUF shard size
Q4_K_M / UD-Q4_K_XL / AWQ (4-bit — Recommended) (UD-Q4_K_XL) 20.82 GiB 0.22 GiB 21.6 GiB (23.19 GB) ~336.5 tok/s Fits with Safe Headroom Arc Pro B60 24GB (24GB) Measured GGUF shard size
GGUF IQ4_XS (4.25-bit — Compact) (IQ4_XS) 16.51 GiB 0.22 GiB 17.29 GiB (18.56 GB) ~355 tok/s Fits with Safe Headroom Arc Pro B60 24GB (24GB) Measured GGUF shard size
GGUF Q3_K_M (3-bit — Low VRAM) (Q3_K_M) 15.46 GiB 0.22 GiB 16.24 GiB (17.44 GB) ~359.8 tok/s Fits with Safe Headroom Arc Pro B60 24GB (24GB) Measured GGUF shard size
GGUF UD-Q2_K_XL (2-bit — Extreme MoE) (UD-Q2_K_XL) 11.45 GiB 0.22 GiB 12.23 GiB (13.13 GB) ~379.5 tok/s Fits with Safe Headroom RTX 4060 Ti 16GB (16GB) Measured GGUF shard size

Technical Specifications & FAQ

Does Qwen3.6 35B-A3B fit on H200 141GB SXM (141GB)?

In 4-bit (UD-Q4_K_XL) at 8,192 context, Qwen3.6 35B-A3B requires 21.6 GiB total GPU memory (20.82 GiB weights + 0.22 GiB KV cache + 0.56 GiB runtime buffers) against 133.9 GiB usable on H200 141GB SXM, delivering ~336.5 tok/s decode.

How much VRAM does Qwen3.6 35B-A3B need at 32K context?

At 32,768 context tokens, Qwen3.6 35B-A3B (Hybrid Linear/Mamba + MoE) allocates 0.69 GiB for KV cache and state, bringing total 4-bit VRAM to 22.07 GiB (23.7 GB decimal).

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