llmrun
Jab1718Qwen 3.8Qwen4ExpForCausalLM

Qwen3.8 Flash Coder 85gb BF16 — Hardware Requirements & GPU Compatibility

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Qwen3.8 Flash Coder 85gb BF16 is a 42.6B-parameter open language model from Jab1718 in the Qwen 3.8 family. It supports a context window of up to 262,144 tokens. At BF16 it needs about 85.62 GB of VRAM — see which GPUs and Macs can run it below.

42.6B params · MoE7.2B active262K contextApache 2.02.9K downloads40 likes

Qwen3.8 Flash Coder 85gb BF16 runs on a 96 GB+ Mac or a workstation GPU

Best local pick → Mac Studio (M3 Ultra, 96GB) · BF16 · 86.2 GB · ~29 tok/s

Macs from96 GB BF16 · ~29 tok/s

Apache 2.0

Not set up for it?

Reference GPU · RTX 4090 24 GB

Estimates, ±20% · how we estimate

Run Qwen3.8 Flash Coder 85gb BF16

One recommended way. Every other method, OS and quant is in the step-by-step guide.

Recommended

vLLM
one command · needs vLLM installed
$vllm serve Jab1718/qwen3.8-flash-coder-85gb-bf16 --max-model-len 16384 --tensor-parallel-size 8

vLLM repo with its own quantisation

Download: Weights on Hugging Face

install, OS, other quants

Other ways

each opens step-by-step

Run in cloud

Fits on H200 (141 GB) (54 GB headroom) · BF16

Generation speed
~137 tok/s
generation speed
Cost per 1M output tokens
$7.27
per 1M output tokens

How Much VRAM Does Qwen3.8 Flash Coder 85gb BF16 Need?

Select a quantization level; the listed hardware adheres to it.

QuantizationVRAM+32KRuns on
85.6 GB86.9 GB16-bit · bfloat — Brain floating point 16 — preferred for trainingRuns on RTX PRO 6000 Blackwell Max-Q Workstation Edition 96 GB
est.calculated, no published file yet

Selected BF16

Brain floating point 16

86.2GBat 16K context

Weights
85.2 GB
KV cache
0.7 GB
Overhead
0.3 GB

Server-class: ~86.2 GB at 16K context · one RTX PRO 6000 Blackwell Max-Q Workstation Edition 96 GB

Or rent H200 from $3.59/hr.

Which Hardware Can Run Qwen3.8 Flash Coder 85gb BF16?

BF16 · 85.6 GB

Qwen3.8 Flash Coder 85gb BF16 (BF16) requires 85.6 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 112+ GB is recommended. Using the full 262K context window can add up to 10.7 GB, bringing total usage to 96.3 GB. No consumer GPU has enough memory. 30 devices with unified memory can run Qwen3.8 Flash Coder 85gb BF16, including Mac Studio (M3 Ultra, 256GB), Mac Studio (M3 Ultra, 512GB), Mac Studio (M3 Ultra, 96GB).

By VRAM tier · typical GPUs and Macs at BF16

Consumer GPUs (up to 32 GB) and Macs up to 64 GB: too small for this model (needs ≥ 86.2 GB)8 GB tier →12 GB tier →16 GB tier →24 GB tier →Macs →

Alternatives to Qwen3.8 Flash Coder 85gb BF16

Qwen 3.8 family · 12 models →

Similar models

3
ModelScoreVRAMWhy it is similar
Phi 3.5 MoE InstructMicrosoft—23.9 GBsame size
Falcon 40B InstructTII UAE—23.8 GBsame size
IQuest Coder V1 40B Loop InstructIQuestLab—85.3 GBsame size

Specifications

Publisher
Jab1718
Family
Qwen 3.8
Parameters
42.6B
Active parameters
7.2B per token
Architecture
Qwen4ExpForCausalLM
Context Length
262,144 tokens
Vocabulary Size
248,320
Release Date
2026-08-27
License
Apache 2.0

Frequently Asked Questions

How much VRAM does Qwen3.8 Flash Coder 85gb BF16 need?

Qwen3.8 Flash Coder 85gb BF16 requires 85.6 GB of VRAM at BF16. Full 262K context adds up to 10.7 GB (96.3 GB total).

VRAM = Weights + KV Cache + Overhead

Weights = 42.6B × 16 bits ÷ 8 = 85.2 GB

KV Cache + Overhead ≈ 0.4 GB (at 2K context + ~0.3 GB framework)

Fit ratings and hardware model lists check this model with room for a 16K-token context, which needs a little more memory.

KV Cache + Overhead ≈ 11.1 GB (at full 262K context)

VRAM usage by quantization

85.6 GB
96.3 GB

Learn more about VRAM estimation →

Can NVIDIA GeForce RTX 5090 run Qwen3.8 Flash Coder 85gb BF16?

No — Qwen3.8 Flash Coder 85gb BF16 requires at least 85.6 GB at BF16, which exceeds the NVIDIA GeForce RTX 5090's 32 GB of VRAM.

Can I run Qwen3.8 Flash Coder 85gb BF16 on a Mac?

Yes — Mac Studio (M3 Ultra, 96GB) and 20 other Macs can run Qwen3.8 Flash Coder 85gb BF16. Apple Silicon uses unified memory, so the model shares RAM with the system. At BF16 you need at least 85.6 GB of usable unified memory (RAM minus macOS overhead).

Can I run Qwen3.8 Flash Coder 85gb BF16 locally?

Yes — Qwen3.8 Flash Coder 85gb BF16 can run locally on consumer hardware. Popular tools include Ollama, LM Studio, and llama.cpp.

How fast is Qwen3.8 Flash Coder 85gb BF16?

At BF16, Qwen3.8 Flash Coder 85gb BF16 can reach ~79 tok/s on AMD Instinct MI350X. Speed depends mainly on GPU memory bandwidth. Real-world results typically within ±20%.

tok/s = 1000 ÷ (active GB ÷ (bandwidth GB/s × efficiency) × 1000 + layers × routing ms)

Mixture-of-Experts: just the active experts get read for each token, along with a fixed routing cost per layer.

Example: NVIDIA B200 → 14.5 GB active ÷ (8000 × 0.65) = 2.79 ms, plus 48 layers × 0.055 ms = 2.64 ms, so 1000 ÷ 5.43 ms = ~184 tok/s

Estimated speed at BF16 (85.6 GB)

~184 tok/s
~184 tok/s
~139 tok/s

Real-world results typically within ±20%. Speed depends on batch size, quantization kernel, and software stack.

Learn more about tok/s estimation →

What's the download size of Qwen3.8 Flash Coder 85gb BF16?

At BF16, the download is about 85.24 GB.

Which GPUs can run Qwen3.8 Flash Coder 85gb BF16?

No single consumer GPU has enough VRAM to run Qwen3.8 Flash Coder 85gb BF16 at BF16 (85.6 GB). Multi-GPU or professional hardware is required.

Which devices can run Qwen3.8 Flash Coder 85gb BF16?

30 devices with unified memory can run Qwen3.8 Flash Coder 85gb BF16 at BF16 (85.6 GB), including ASUS Ascent GX10, Beelink GTR9 Pro (Ryzen AI Max+ 395, 128 GB), Framework Desktop (Ryzen AI Max+ 395, 128 GB), GMKtec EVO-X2 (Ryzen AI Max+ 395, 128 GB). Apple Silicon Macs use unified memory shared between CPU and GPU, making them well-suited for local LLM inference.