Qwen3 4B Heretic — Hardware Requirements & GPU Compatibility
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Qwen3 4B Heretic is a 4.0B-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 2.90 GB of VRAM — see which GPUs and Macs can run it below.
773 downloads
4 likesSpecifications
- Publisher
- DreamFast
- Family
- Qwen 3
- Parameters
- 4.0B
- Architecture
- Qwen3ForCausalLM
- Context Length
- 40,960 tokens
- Vocabulary Size
- 151,936
- Release Date
- 2026-03-10
- License
- Apache 2.0
Get Started
HuggingFace
How Much VRAM Does Qwen3 4B Heretic Need?
Select a quantization to see compatible GPUs below.
| Quantization | Bits | VRAM | + Context | File Size | Quality |
|---|---|---|---|---|---|
| Q2_Kest. | 3.40 | 2.2 GB | 5.8 GB | 1.71 GB | 2-bit quantization with K-quant improvements |
| Q3_K_M | 3.90 | 2.5 GB | 6.0 GB | 1.96 GB | 3-bit medium quantization |
| Q4_K_S | 4.50 | 2.8 GB | 6.3 GB | 2.26 GB | 4-bit small quantization |
| Q4_K_M | 4.80 | 2.9 GB | 6.5 GB | 2.41 GB | 4-bit medium quantization — most popular sweet spot |
| Q5_K_S | 5.50 | 3.3 GB | 6.8 GB | 2.77 GB | 5-bit small quantization |
| Q5_K_M | 5.70 | 3.4 GB | 6.9 GB | 2.87 GB | 5-bit medium quantization — good quality/size tradeoff |
| Q6_K | 6.60 | 3.8 GB | 7.4 GB | 3.32 GB | 6-bit quantization, very good quality |
| Q8_0 | 8.00 | 4.5 GB | 8.1 GB | 4.02 GB | 8-bit quantization, near-lossless |
| BF16est. | 16.00 | 8.5 GB | 12.1 GB | 8.04 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 4B Heretic?
Q4_K_M · 2.9 GBQwen3 4B Heretic (Q4_K_M) requires 2.9 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 4+ GB is recommended. Using the full 41K context window can add up to 3.6 GB, bringing total usage to 6.5 GB. 50 GPUs can run it, including NVIDIA GeForce RTX 5090, NVIDIA GeForce RTX 3090 Ti.
Runs great
— Plenty of headroomWhich Devices Can Run Qwen3 4B Heretic?
Q4_K_M · 2.9 GB59 devices with unified memory can run Qwen3 4B Heretic, including NVIDIA DGX H100, NVIDIA DGX A100 640GB.
Runs great
— Plenty of headroomRelated Models
Frequently Asked Questions
- How much VRAM does Qwen3 4B Heretic need?
Qwen3 4B Heretic requires 2.9 GB of VRAM at Q4_K_M, or 8.5 GB at BF16. Full 41K context adds up to 3.6 GB (6.5 GB total).
VRAM = Weights + KV Cache + Overhead
Weights = 4.0B × 4.8 bits ÷ 8 = 2.4 GB
KV Cache + Overhead ≈ 0.5 GB (at 2K context + ~0.3 GB framework)
KV Cache + Overhead ≈ 4.1 GB (at full 41K context)
VRAM usage by quantization
Q4_K_M2.9 GBQ4_K_M + full context6.5 GB- What's the best quantization for Qwen3 4B Heretic?
For Qwen3 4B Heretic, Q4_K_M (2.9 GB) offers the best balance of quality and VRAM usage. Q5_K_S (3.3 GB) provides better quality if you have the VRAM. The smallest option is Q2_K at 2.2 GB.
VRAM requirement by quantization
Q2_K2.2 GBQ4_K_S2.8 GBQ4_K_M ★2.9 GBQ5_K_S3.3 GBQ6_K3.8 GBBF168.5 GB★ Recommended — best balance of quality and VRAM usage.
- Can I run Qwen3 4B Heretic on a Mac?
Qwen3 4B Heretic requires at least 2.2 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 4B Heretic locally?
Yes — Qwen3 4B Heretic can run locally on consumer hardware. At Q4_K_M quantization it needs 2.9 GB of VRAM. Popular tools include Ollama, LM Studio, and llama.cpp.
- How fast is Qwen3 4B Heretic?
At Q4_K_M, Qwen3 4B Heretic can reach ~1517 tok/s on AMD Instinct MI350X. On NVIDIA GeForce RTX 4090: ~226 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 ÷ 2.9 × 0.65 = ~1793 tok/s
Estimated speed at Q4_K_M (2.9 GB)
~1793 tok/s~226 tok/s~1793 tok/s~1517 tok/sReal-world results typically within ±20%. Speed depends on batch size, quantization kernel, and software stack.
- What's the download size of Qwen3 4B Heretic?
At Q4_K_M, the download is about 2.41 GB. The full-precision BF16 version is 8.04 GB. The smallest option (Q2_K) is 1.71 GB.
- Which GPUs can run Qwen3 4B Heretic?
50 consumer GPUs can run Qwen3 4B Heretic at Q4_K_M (2.9 GB). Top options include AMD Radeon RX 6700 XT, AMD Radeon RX 6800, AMD Radeon RX 6800 XT. 50 GPUs have plenty of headroom for comfortable inference.
- Which devices can run Qwen3 4B Heretic?
59 devices with unified memory can run Qwen3 4B Heretic at Q4_K_M (2.9 GB), including AMD Ryzen AI 9 HX 370 (Strix Point) Laptop, ASUS Ascent GX10, Apple iPhone 17 Pro, Asus ROG Flow Z13 (2025, 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.