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DreamFastQwen 3Qwen3ForCausalLM

Qwen3 8B Heretic — Hardware Requirements & GPU Compatibility

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Qwen3 8B Heretic is a 8.2B-parameter open language model from DreamFast in the Qwen 3 family. It supports a context window of up to 40,960 tokens. At Q4_K_M it needs about 5.52 GB of VRAM — see which GPUs and Macs can run it below.

8.2B params · dense41K contextApache 2.05.7K downloads43 likes
Based on Qwen3 8B
S

Runs great on a 24 GB GPU

Runs from8 GB Q4_K_M · 16KBest on24 GB Q4_K_M · ~119 tok/s · 40KMacs from16 GB Q4_K_M · ~25 tok/s

Apache 2.0

Reference GPU · RTX 4090 24 GB

Estimates, ±20% · how we estimate

Run Qwen3 8B Heretic

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 DreamFast/qwen3-8b-heretic --max-model-len 16384

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 RTX 3060 12GB (4 GB headroom) · Q4_K_M

Generation speed
~42 tok/s
generation speed
Cost per 1M output tokens
$0.45
per 1M output tokens

How Much VRAM Does Qwen3 8B Heretic Need?

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

QuantizationVRAM+32KOn RTX 4090 (reference)
4.1 GB8.6 GB2-bit · K-quant — 2-bit quantization with K-quant improvementsFits: 40K context · ~161 tok/s
4.6 GB9.1 GB3-bit medium — 3-bit medium quantizationFits: 40K context · ~143 tok/s
5.2 GB9.7 GB4-bit small — 4-bit small quantizationFits: 40K context · ~126 tok/s
5.5 GB10.1 GB4-bit medium — 4-bit medium quantization — most popular sweet spotFits: 40K context · ~119 tok/s
6.2 GB10.8 GB5-bit small — 5-bit small quantizationFits: 40K context · ~105 tok/s
6.4 GB11 GB5-bit medium — 5-bit medium quantization — good quality/size tradeoffFits: 40K context · ~102 tok/s
7.4 GB11.9 GB6-bit, very good — 6-bit quantization, very good qualityFits: 40K context · ~89 tok/s
8.8 GB13.3 GB8-bit, near-lossless — 8-bit quantization, near-losslessFits: 40K context · ~75 tok/s
17.0 GB21.5 GB16-bit · bfloat — Brain floating point 16 — preferred for trainingFits: 40K context · ~39 tok/s
est.calculated, no published file yet

Selected Q4_K_M

4-bit medium quantization

7.6GBat 16K context

Weights
4.9 GB
KV cache
2.4 GB
Overhead
0.3 GB

Fits RTX 4090 (reference) · 16.4 GB free · ~119 tok/s

≥50 tok/s needs ≥424 GB/s · RTX 5090 ~211, RTX 3090 Ti ~119

Which Hardware Can Run Qwen3 8B Heretic?

Q4_K_M · 5.5 GB

Qwen3 8B Heretic (Q4_K_M) requires 5.5 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 8+ GB is recommended. Using the full 41K context window can add up to 5.7 GB, bringing total usage to 11.3 GB. 52 GPUs can run it, including NVIDIA GeForce RTX 5090, NVIDIA GeForce RTX 3090 Ti, NVIDIA GeForce RTX 3070 Ti. 151 devices with unified memory can run Qwen3 8B Heretic, including Mac Studio (M3 Ultra, 256GB), Mac Studio (M3 Ultra, 512GB), NVIDIA Jetson Orin Nano 8GB (Super).

By VRAM tier · typical GPUs and Macs at Q4_K_M
8 GB · RTX 4060Q4_K_M · 7.6 GB · ~32 tok/s · 16K8 GB tier →
12 GB · RTX 3060 12GBQ4_K_M · 7.6 GB · ~42 tok/s · 40K12 GB tier →
16 GB · RTX 5060 Ti 16GBQ4_K_M · 7.6 GB · ~53 tok/s · 40K16 GB tier →
24 GB · RTX 4090referenceQ4_K_M · 7.6 GB · ~119 tok/s · 40K24 GB tier →
Mac 32 GB · Mac Mini M4Q4_K_M · 7.6 GB · ~15 tok/s · 40KMacs →
Mac 64 GB · Mac Studio M4 MaxQ4_K_M · 7.6 GB · ~69 tok/s · 40KMacs →

Alternatives to Qwen3 8B Heretic

Qwen 3 family · 77 models →

Similar models

6
ModelScoreVRAMtok/sWhy it is similar
Granite Switch 4.1 8BIBM—20.7 GB~36same size
ALoDLM 8BAmazon—7.6 GB~119same size
Llm Jp 4.1 8B Thinkingllm-jp—7.6 GB~115same size
Ling 3.0 TinyInclusion AI—5.5 GB~364same size
LFM2.5 8B A1BLiquid AI—5.6 GB~335same size
BitCPM CANN 8BOpenBMB—5.6 GB~127same size

Specifications

Publisher
DreamFast
Family
Qwen 3
Parameters
8.2B
Architecture
Qwen3ForCausalLM
Context Length
40,960 tokens
Vocabulary Size
151,936
Release Date
2026-03-20
License
Apache 2.0

Frequently Asked Questions

How much VRAM does Qwen3 8B Heretic need?

Qwen3 8B Heretic requires 5.5 GB of VRAM at Q4_K_M, or 17.0 GB at BF16. Full 41K context adds up to 5.7 GB (11.3 GB total).

VRAM = Weights + KV Cache + Overhead

Weights = 8.2B × 4.8 bits ÷ 8 = 4.9 GB

KV Cache + Overhead ≈ 0.6 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 ≈ 6.4 GB (at full 41K context)

VRAM usage by quantization

5.5 GB
11.3 GB

Learn more about VRAM estimation →

What's the best quantization for Qwen3 8B Heretic?

For Qwen3 8B Heretic, Q4_K_M (5.5 GB) offers the best balance of quality and VRAM usage. Q5_K_S (6.2 GB) provides better quality if you have the VRAM. The smallest option is Q2_K at 4.1 GB.

VRAM requirement by quantization

Q2_K
4.1 GB
Q4_K_S
5.2 GB
Q4_K_M ★
5.5 GB
Q5_K_S
6.2 GB
Q6_K
7.4 GB
BF16
17.0 GB

★ Recommended — best balance of quality and VRAM usage.

Learn more about quantization →

Can I run Qwen3 8B Heretic on a Mac?

Yes — Mac Mini M2 Pro (16 GB) and 133 other Macs can run Qwen3 8B Heretic. Apple Silicon uses unified memory, so the model shares RAM with the system. At Q4_K_M you need at least 5.5 GB of usable unified memory (RAM minus macOS overhead).

Can I run Qwen3 8B Heretic locally?

Yes — Qwen3 8B Heretic can run locally on consumer hardware. Popular tools include Ollama, LM Studio, and llama.cpp.

How fast is Qwen3 8B Heretic?

At Q4_K_M, Qwen3 8B Heretic can reach ~870 tok/s on AMD Instinct MI350X. On NVIDIA GeForce RTX 4090: ~119 tok/s. Speed depends mainly on GPU memory bandwidth. Real-world results typically within ±20%.

tok/s = (bandwidth GB/s ÷ model GB) × efficiency

Example: NVIDIA B200 → 8000 ÷ 5.52 × 0.65 = ~942 tok/s

Estimated speed at Q4_K_M (5.5 GB)

~942 tok/s
~119 tok/s
~942 tok/s
~870 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 8B Heretic?

At Q4_K_M, the download is about 4.91 GB. The full-precision BF16 version is 16.38 GB. The smallest option (Q2_K) is 3.48 GB.

Which GPUs can run Qwen3 8B Heretic?

52 consumer GPUs can run Qwen3 8B Heretic at Q4_K_M. Top options include AMD Radeon RX 6700 XT, AMD Radeon RX 6800, AMD Radeon RX 6800 XT, AMD Radeon RX 7600. 40 GPUs have plenty of headroom for comfortable inference.

Which devices can run Qwen3 8B Heretic?

151 devices with unified memory can run Qwen3 8B Heretic at Q4_K_M (5.5 GB), including AMD Ryzen AI 9 HX 370 (Strix Point) Laptop, ASUS Ascent GX10, Beelink GTR9 Pro (Ryzen AI Max+ 395, 128 GB), Framework Desktop (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.