GestaltLabs/Ornstein-Hermes-3.6-27b-GGUF
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Ornstein-hermes-3.6-27b — GGUF Quantizations
GGUF quantizations of GestaltLabs/Ornstein-hermes-3.6-27b — a Hermes-format function-calling fine-tune of Ornstein-3.6-27B (Qwen 3.6 27B multimodal).
All K- and I-quants are calibrated with an imatrix computed from 800 high-quality Hermes-format tool-use conversations sampled from DJLougen/Acta-Synthetic — so the quantization gradients are tuned for tool-calling distributions, not generic web text.
Support This Work
I'm a PhD student in visual neuroscience at the University of Toronto who also happens to spend way too much time fine-tuning, merging, and quantizing open-weight models on rented H100s and a local DGX Spark. All training compute is self-funded — balancing GPU costs against a student budget. If my uploads have been useful to you, consider buying a PhD student a coffee. It goes a long way toward keeping these experiments running.
Available Quants
| Quant | Bits/weight | Size | Notes |
|---|---|---|---|
Q8_0 | ~8.5 | 26.6 GB | Near-lossless. Use if you have ≥32 GB VRAM/RAM. |
Q6_K | ~6.6 | 20.6 GB | High fidelity, very small loss vs F16. |
Q5_K_M | ~5.7 | 17.9 GB | Strong default for ≥24 GB cards. |
Q4_K_M | ~4.8 | 15.4 GB | Most popular 4-bit; great quality/size tradeoff. |
IQ4_NL | ~4.5 | 14.7 GB | imatrix-aware non-linear 4-bit, smaller than Q4_K_M. |
IQ4_XS | ~4.3 | 14.0 GB | Smallest 4-bit; minor quality drop vs Q4_K_M. |
Q3_K_M | ~3.9 | 12.4 GB | Aggressive but usable; ≥16 GB VRAM. |
IQ3_M | ~3.7 | 11.7 GB | imatrix 3-bit; better than Q3_K_M at similar size. |
IQ2_M | ~2.7 | 9.3 GB | Tight VRAM budget; expect noticeable degradation. |
Picking a quant
- 24 GB GPU (e.g. RTX 3090/4090) →
Q4_K_MorIQ4_NL - 32 GB (e.g. RTX 5090) →
Q5_K_M - 48 GB (e.g. RTX A6000) →
Q6_K - 80 GB (H100/A100) →
Q8_0 - CPU-only with 32 GB RAM →
IQ4_XSorQ3_K_M - 16 GB VRAM →
IQ3_MorIQ2_M
Usage
llama.cpp
./llama-cli -m Ornstein-hermes-3.6-27b-Q4_K_M.gguf \
-ngl 999 \
-c 8192 \
--temp 0.7 \
-p "<|im_start|>user\nWhat's the weather in Tokyo?<|im_end|>\n<|im_start|>assistant\n"
For tool calling, register tools via the --chat-template system prompt or use the OpenAI-compatible server (llama-server) which handles tool registration automatically.
Ollama
ollama create ornstein-hermes-q4 -f - <<EOF
FROM ./Ornstein-hermes-3.6-27b-Q4_K_M.gguf
TEMPLATE """{{- range .Messages }}<|im_start|>{{ .Role }}
{{ .Content }}<|im_end|>
{{ end }}<|im_start|>assistant
"""
PARAMETER stop "<|im_end|>"
EOF
ollama run ornstein-hermes-q4
LM Studio
- Download any GGUF from this repo
- Open in LM Studio (auto-detects Qwen3 chat template)
- Use the built-in tool-calling interface
Hermes Tool-Calling Format
The model was trained on Hermes-style function calling. Expected message flow:
<|im_start|>system
You are a function calling AI model. You are provided with function signatures within <tools></tools> XML tags.
<tools>
[{"name": "get_weather", "description": "...", "parameters": {...}}]
</tools>
<|im_end|>
<|im_start|>user
What's the weather in Tokyo?<|im_end|>
<|im_start|>assistant
<think>The user wants weather info. I'll call get_weather.</think>
<tool_call>{"name": "get_weather", "arguments": {"city": "Tokyo"}}</tool_call><|im_end|>
<|im_start|>tool
<tool_response>{"temp_c": 18, "condition": "cloudy"}</tool_response><|im_end|>
<|im_start|>assistant
It's 18°C and cloudy in Tokyo.<|im_end|>
Quantization Details
| Source | GestaltLabs/Ornstein-hermes-3.6-27b (bf16) |
| F16 GGUF size | 53.8 GB (851 tensors) |
| Tool | llama.cpp (latest) |
| imatrix corpus | 800 conversations from DJLougen/Acta-Synthetic, passes_thresholds=True, rendered with the Qwen3.6 chat template (~385K tokens, 1.74 MB) |
| imatrix params | --n-gpu-layers 999 -c 4096 -b 4096 --chunks 200 |
| Hardware | 1× NVIDIA RTX PRO 6000 Blackwell |
License
Apache 2.0 — inherited from Qwen 3.6 base.
Citation
If you use this model, please consider citing the dataset:
@dataset{lougen_acta_2026,
author = {DJLougen},
title = {Acta: A Premium Curated Sample of High-Quality Agentic Tool-Use Conversations},
year = {2026},
url = {https://huggingface.co/datasets/DJLougen/Acta}
}
