SAVRN
Search Contact SAVRN

Open-weight model · Text generation

Ornith-1.5-35B-A3B-NVFP4

by Ornith ornith-ai/Ornith-1.5-35B-A3B-NVFP4

Chirp Chirp! We are introducing Ornith-1.5, a major step toward building foundation models through end-to-end self-improvement.

Parameters19.5B
Context262,144
Weights23.4 GB
Licensemit
AccessOpen weights
Monthly Downloads1.1M

Runs On

What it takes to serve Ornith-1.5-35B-A3B-NVFP4 (19.5B parameters): the memory its weights need at each precision, and the cheapest way to rent enough data-center GPUs to hold them.

PrecisionWeightsMemory neededCheapest setupPer hourAlso fits
16-bit 39.1 GB 46.9 GB 1x MI300X (192 GB)
Vultr
$1.85 1x H100 $1.99 · 1x MI325X $2.00
8-bit 19.5 GB 23.4 GB 1x MI300X (192 GB)
Vultr
$1.85 1x H100 $1.99 · 1x MI325X $2.00
4-bit 9.8 GB 11.7 GB 1x MI300X (192 GB)
Vultr
$1.85 1x H100 $1.99 · 1x MI325X $2.00

Memory is the weights at that precision plus 20% for the runtime and a short context; a long context needs more. Prices are the lowest on-demand hourly rates in the SAVRN Index, read Sep 18, 2026.

SAVRN's Notes on Ornith-1.5-35B-A3B-NVFP4

Eight of 256 experts fire on each token. With 19.5B parameters listed, memory comes to 46.9 GB at 16-bit, 23.4 GB at 8-bit, 11.7 GB at 4-bit. All three fit the cheapest setup on our board, one 192 GB MI300X at $1.85 per hour on-demand, leaving the rest of the card to budget for the 262,144 token context. Ornith built it for text generation and trained it through a self-improvement loop that generates its own tasks.

MIT is as light as a license gets: commercial use, modification and redistribution, keeping only the copyright and permission notices. Two things to check. The name says NVFP4 and 35B, yet the 22 files total about 23.5 GB and the 4-bit row reads 9.8 GB of weights, so confirm the precision you are loading. The lineage runs through Ornith-1.0 to Qwen3.5 and Gemma4 with no base-model relation recorded, so confirm the upstream terms yourself.

Model Card

By Ornith, published under mit, revision 94e431d9cc47.

Ornith-1.5-35B-A3B

Chirp Chirp! We are introducing Ornith-1.5, a major step toward building foundation models through end-to-end self-improvement.

Ornith-1.5 extends Ornith-1.0 (which was developed on top of Qwen3.5 and Gemma4 with additional continued pretraining, mid-training, and post-training) by expanding the self-improvement loop from scaffold and rollout optimization to jointly optimizing task generation, scaffold construction, and solution rollouts. Rather than relying on a fixed set of human-curated tasks and manually designed harnesses, Ornith-1.5 continuously generates new training tasks, discovers effective strategies for solving them, and improves the policy through reinforcement learning. For more details on the task, harness, and rollout reward design, please refer to our blog.

Ornith 1.5 35B-A3B

Read the full model card (1,476 words)

Configuration

Architecture
Qwen3_5MoeForConditionalGeneration
Context length (tokens)
262,144
Layers
40
Hidden size
2,048
Attention heads
16
Key/value heads
2
Head dimension
256
Vocabulary size
248,320
Experts
256
Experts active per token
8
Model type
qwen3_5_moe
Quantization
modelopt

Identity and Version

Repository
ornith-ai/Ornith-1.5-35B-A3B-NVFP4
Publisher
Ornith
Task
Text generation
Modality
Text
Library
transformers
Parameters
19.5B parameters
Languages
Not stated by the source
Revision
94e431d9cc47fa1986a7a1a4e9a80f7f118b03aa
First published
2026-08-18
Last updated
2026-08-26

Files and Weights

22 files, 23.5 GB in total. The weights are 3 files totalling 23.4 GB in safetensors.

Weights3 files · 23.4 GB
Configuration7 files · 10.5 MB
Tokenizer4 files · 22.9 MB
Documentation1 file · 29.9 KB
Other3 files · 1.7 MB
Repository4 files · 4.7 MB
Every file
FileTypeSizeSHA-256
model-00001-of-00003.safetensorsWeights10.0 GB 648fe8317148
model-00002-of-00003.safetensorsWeights10.0 GB cb5c5978721a
model-00003-of-00003.safetensorsWeights3.4 GB 8303cef7d375
config.jsonConfiguration58.2 KB
generation_config.jsonConfiguration202 B
hf_quant_config.jsonConfiguration42.2 KB
model.safetensors.index.jsonConfiguration10.4 MB
preprocessor_config.jsonConfiguration390 B
processor_config.jsonConfiguration1.2 KB
video_preprocessor_config.jsonConfiguration385 B
README.mdDocumentation29.9 KB
assets/ornith_35b_eval.pngOther709.4 KB 758a8f72b41a
assets/ornith_logo.pngOther962.4 KB 458ee0d85bae
chat_template.jinjaOther7.5 KB
.gitattributesRepository1.8 KB
.model_only_prunedRepository
.quant_summary.txtRepository4.7 MB
.sync_completeRepository295 B
merges.txtTokenizer3.4 MB
tokenizer.jsonTokenizer12.8 MB 5f9e4d4901a9
tokenizer_config.jsonTokenizer16.7 KB
vocab.jsonTokenizer6.7 MB

License and Download

License
mit
Access
Open weights, no gate
Download size
23.4 GB
Download from Ornith

Released by Ornith through its official repository on Hugging Face. Read the license.

Memory Requirements

PrecisionWeights in memory
As published23.4 GB
16-bit39.1 GB
8-bit19.5 GB
4-bit9.8 GB

Weights only, from the published parameter count; the key-value cache and runtime add to this.

Compare Ornith-1.5-35B-A3B-NVFP4

Questions About Ornith-1.5-35B-A3B-NVFP4

How much GPU memory does Ornith-1.5-35B-A3B-NVFP4 need?

About 46.9 GB at 16-bit and 11.7 GB at 4-bit: the weights (19.5B parameters) plus a working margin. A long context needs more.

What is the cheapest GPU to run Ornith-1.5-35B-A3B-NVFP4 on?

At 16-bit, 1x MI300X from $1.85 an hour; at 4-bit, 1x MI300X from $1.85 an hour, at the lowest on-demand prices the SAVRN Index lists.

Can I use Ornith-1.5-35B-A3B-NVFP4 commercially?

Yes. Ornith-1.5-35B-A3B-NVFP4 is released under MIT License. The MIT License is a short permissive license. It permits commercial use, modification and redistribution, provided the copyright notice and permission notice are included.

What is Ornith-1.5-35B-A3B-NVFP4's context length?

262,144 tokens, from the maximum position embeddings in its published configuration.

Similar Models

Model · Text generation

Qwen3.6-35B-A3B-NVFP4

NVIDIA

The NVIDIA Qwen3.6-35B-A3B-NVFP4 model is the quantized version of Alibaba's Qwen3.6-35B-A3B model, which is an auto-regressive language model that uses an optimized transformer architecture. For more information, please check here. The NVIDIA Qwen3.6-35B-A3B-NVFP4 model is quantized with Model Optimizer. This model is ready for commercial/non-commercial use. This model is not owned or developed by NVIDIA. This model has been developed and built to a third-party’s requirements for this application and use case; see link to Non-NVIDIA (Qwen3.6-35B-A3B) Model Card from Alibaba. Global Developers looking to take off-the-shelf, pre-quantized models for deployment in AI Agent systems, chatbots…

Open weights apache-2.0 18.7B parameters 262,144 tokens Model Optimizer

Model · Text generation

gpt-neox-20b

EleutherAI

GPT-NeoX-20B is a 20 billion parameter autoregressive language model trained on the Pile using the GPT-NeoX library. Its architecture intentionally resembles that of GPT-3, and is almost identical to that of GPT-J- 6B. Its training dataset contains a multitude of English-language texts, reflecting the general-purpose nature of this model. See the accompanying paper for details about model architecture (including how it differs from GPT-3), training procedure, and additional evaluations. Model](https://arxiv.org/abs/2204.06745). For details about the training dataset, see the Pile paper, and its data sheet. Discord](https://discord.gg/zBGx3azzUn), and post them in #release-discussion. Please…

Open weights apache-2.0 20.7B parameters 2,048 tokens transformers

Model · Text generation

NVIDIA-Nemotron-3-Nano-30B-A3B-NVFP4

NVIDIA

September 2025 \- December 2025 The post-training data has a cutoff date of November 28, 2025\. The pre-training data has a cutoff date of June 25, 2025\. Nemotron-Nano-3-30B-A3B-NVFP4 is a quantized version of Nemotron-Nano-3-30B-A3B and is a large language model (LLM) trained from scratch by NVIDIA, and designed as a unified model for both reasoning and non-reasoning tasks. It responds to user queries and tasks by first generating a reasoning trace and then concluding with a final response. The model's reasoning capabilities can be configured through a flag in the chat template. If the user prefers the model to provide its final answer without intermediate reasoning traces, it can be…

Open weights other 18.2B parameters 262,144 tokens transformers

Model · Text generation

Gemma-4-31B-IT-NVFP4

NVIDIA

Gemma 4 31B IT is an open multimodal model built by Google DeepMind that handles text and image inputs, can process video as sequences of frames, and generates text output. It is designed to deliver frontier-level performance for reasoning, agentic workflows, coding, and multimodal understanding on consumer GPUs and workstations, with a 256K-token context window and support for over 140 languages. The model uses a hybrid attention mechanism that interleaves local sliding-window and full global attention, with unified Keys and Values in global layers and Proportional RoPE (p-RoPE) to support long-context performance. The NVIDIA Gemma 4 31B IT NVFP4 model is quantized with NVIDIA Model…

Open weights other 20.9B parameters 262,144 tokens Model Optimizer

Model · Text generation

gpt-oss-20b

OpenAI

Welcome to the gpt-oss series, OpenAI’s open-weight models designed for powerful reasoning, agentic tasks, and versatile developer use cases. We’re releasing two flavors of these open models: - gpt-oss-120b — for production, general purpose, high reasoning use cases that fit into a single 80GB GPU (like NVIDIA H100 or AMD MI300X) (117B parameters with 5.1B active parameters) - gpt-oss-20b — for lower latency, and local or specialized use cases (21B parameters with 3.6B active parameters) Both models were trained on our harmony response format and should only be used with the harmony format as it will not work correctly otherwise. You can use gpt-oss-120b and gpt-oss-20b with Transformers.…

Open weights apache-2.0 20.9B parameters 131,072 tokens transformers

The pre-training data has a cutoff date of September 2025. The post-training data has a cutoff date of May 2026. NVIDIA Nemotron™ is a family of open models with open weights, training data, and recipes, delivering leading efficiency and accuracy for building specialized AI agents. NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4 is a large language model (LLM) trained by NVIDIA. The model employs a hybrid Mixture-of-Experts architecture, utilizing interleaved Mamba-2 and MoE layers, along with select Attention layers. The Lightning 3.5 model is released alongside a number of speculative decoding methods for faster text generation. The model has 3B active parameters and 30B parameters in total.…

Open weights other 17.8B parameters 1,048,576 tokens transformers