# Swift-1.5-Qwen3.8-27b-Quark-RTN-MXFP4 by Ethan Todd
Source: https://savrn.com/models/swift-1-5-qwen3-8-27b-quark-rtn-mxfp4
Markdown alternate of the page above; the site index is https://savrn.com/llms.txt

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## Runs On

What it takes to serve Swift-1.5-Qwen3.8-27b-Quark-RTN-MXFP4 (15.6B parameters): the memory its weights need at each precision, and the cheapest way to rent enough data-center GPUs to hold them.

| Precision | Weights | Memory needed | Cheapest setup | Per hour | Also fits |
| --- | --- | --- | --- | --- | --- |
| 16-bit | 31.2 GB | 37.5 GB | 1x [MI300X](https://savrn.com/ai-index/pricing/gpus/mi300x) (192 GB) Vultr | $1.85 | [1x H100](https://savrn.com/ai-index/pricing/gpus/h100) $1.99 · [1x MI325X](https://savrn.com/ai-index/pricing/gpus/mi325x) $2.00 |
| 8-bit | 15.6 GB | 18.7 GB | 1x [MI300X](https://savrn.com/ai-index/pricing/gpus/mi300x) (192 GB) Vultr | $1.85 | [1x H100](https://savrn.com/ai-index/pricing/gpus/h100) $1.99 · [1x MI325X](https://savrn.com/ai-index/pricing/gpus/mi325x) $2.00 |
| 4-bit | 7.8 GB | 9.4 GB | 1x [MI300X](https://savrn.com/ai-index/pricing/gpus/mi300x) (192 GB) Vultr | $1.85 | [1x H100](https://savrn.com/ai-index/pricing/gpus/h100) $1.99 · [1x MI325X](https://savrn.com/ai-index/pricing/gpus/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](https://savrn.com/ai-index/pricing/gpus), read Oct 7, 2026.

[Swift-1.5-Qwen3.8-27b-Quark-RTN-MXFP4 on every accelerator the SAVRN Index prices, at every precision](https://savrn.com/models/swift-1-5-qwen3-8-27b-quark-rtn-mxfp4/gpus)

## Model Card

quantized to OCP MXFP4 4-bit weights in the same Quark checkpoint container as The weights are plain RTN, not AWQ: see the note below. The 15 MTP tensors are kept in BF16; the radiance runtime loads them with RADIANCEQUARKBF16MTP=1. Why RTN instead of AWQ. The first build of this checkpoint used AWQ with the same smoothing recipe as AMD's release. The AWQ fold itself was mathematically consistent, but on this model a few layers converged to weights to 32-element MXFP4 blocks then destroyed those layers on real, outlier-carrying inputs (layer 7 output relative error ~324), and repairing the worst layers individually was not enough; the remaining smoothed layers still accumulated too much…

Excerpt from the card by Ethan Todd, licensed other.

## Configuration

Architecture

Qwen3_5ForConditionalGeneration

Context length (tokens)

262,144

Layers

64

Hidden size

5,120

Feed-forward size

17,408

Attention heads

24

Key/value heads

4

Head dimension

256

Vocabulary size

248,320

Model type

qwen3_5

Quantization

quark

## Identity and Version

Repository

ethantodd4l/Swift-1.5-Qwen3.8-27b-Quark-RTN-MXFP4

Publisher

Ethan Todd

Task

Image and text to text

Modality

Image and text

Library

transformers

Parameters

15.6B parameters

Languages

Not stated by the source

Revision

3cd117e0d4b1499324bf92479cf2ca30b463041e

First published

2026-10-03

Last updated

2026-10-04

## Files and Weights

14 files, 19.8 GB in total. The weights are 1 file totalling 19.8 GB in safetensors.

Weights1 file · 19.8 GB

Configuration4 files · 12.0 KB

Tokenizer4 files · 22.9 MB

Documentation3 files · 21.9 KB

Other1 file · 9.0 KB

Repository1 file · 1.7 KB

Every file

| File | Type | Size | SHA-256 |
| --- | --- | --- | --- |
| model.safetensors | Weights | 19.8 GB | 74b8f551511d |
| config.json | Configuration | 11.0 KB | — |
| generation_config.json | Configuration | 214 B | — |
| preprocessor_config.json | Configuration | 390 B | — |
| video_preprocessor_config.json | Configuration | 385 B | — |
| LICENSE | Documentation | 13.3 KB | — |
| NOTICE | Documentation | 1.5 KB | — |
| README.md | Documentation | 7.0 KB | — |
| chat_template.jinja | Other | 9.0 KB | — |
| .gitattributes | Repository | 1.7 KB | — |
| merges.txt | Tokenizer | 3.4 MB | — |
| tokenizer.json | Tokenizer | 12.8 MB | 0997f410c57a |
| tokenizer_config.json | Tokenizer | 17.9 KB | — |
| vocab.json | Tokenizer | 6.7 MB | — |

## License and Download

License

other

Access

Open weights, no gate

Download size

19.8 GB

[Download from Ethan Todd](https://huggingface.co/ethantodd4l/Swift-1.5-Qwen3.8-27b-Quark-RTN-MXFP4)

Released by Ethan Todd through its official repository on Hugging Face. [Read the license](https://huggingface.co/ukisai/Swift-1.5-Qwen3.8-27b/blob/main/LICENSE).

## Built From

- Derived from ukisai/Swift-1.5-Qwen3.8-27b
- Quantized from ukisai/Swift-1.5-Qwen3.8-27b

## Memory Requirements

| Precision | Weights in memory |
| --- | --- |
| As published | 19.8 GB |
| 16-bit | 31.2 GB |
| 8-bit | 15.6 GB |
| 4-bit | 7.8 GB |

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

## Questions About Swift-1.5-Qwen3.8-27b-Quark-RTN-MXFP4

### How much GPU memory does Swift-1.5-Qwen3.8-27b-Quark-RTN-MXFP4 need?

About 37.5 GB at 16-bit and 9.4 GB at 4-bit: the weights (15.6B parameters) plus a working margin. A long context needs more.

### What is the cheapest GPU to run Swift-1.5-Qwen3.8-27b-Quark-RTN-MXFP4 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.

### What license is Swift-1.5-Qwen3.8-27b-Quark-RTN-MXFP4 released under?

other, as its publisher declares it. Read the license text before commercial use.

### What is Swift-1.5-Qwen3.8-27b-Quark-RTN-MXFP4's context length?

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

## Similar Models

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## Ethan Todd

[All models and datasets](https://savrn.com/model-publishers/ethantodd4l)

## Versions

- [3cd117e0d4b1](https://savrn.com/models/swift-1-5-qwen3-8-27b-quark-rtn-mxfp4/versions/3cd117e0d4b1) · current 2026-10-04

## Explore More

- [All image and text to text models](https://savrn.com/models/tasks/image-and-text-to-text)
- [Model comparisons](https://savrn.com/models/comparisons)
- [The model directory](https://savrn.com/models)
- [Open model prices by host](https://savrn.com/ai-index/pricing/open-models)

## Source

- Repository metadata, read 2026-10-04.
- [Hugging Face record](https://huggingface.co/ethantodd4l/Swift-1.5-Qwen3.8-27b-Quark-RTN-MXFP4)
- [How the hub is built](https://savrn.com/model-hub/methodology)
