MiniMax-H3 ModelOpt Mixed Dynamic FP8
This repository contains mixed BF16/FP8 derivatives of both MiniMax-H3 video generation partitions:
- FL2VA, at the repository root, supports T2VA/FL2VA and targets an effective precision of 9.0 bits.
- Ref2VA, under
Ref2VA/, supports reference-conditioned video and audio generation and targets an effective transformer precision of 9.25 bits.
The checkpoints target single-GPU vLLM-Omni serving. CPU component offload is recommended on GPUs that cannot hold all resident components.
License: these derivatives remain subject to the MiniMax H3 Community License Agreement in LICENSE, including its territorial, redistribution, notice, and acceptable-use requirements. Review that license before using or redistributing this model.
Runtime format
| Setting | Value |
|---|---|
| Weight format | FP8 E4M3 for selected Linear weights; BF16 otherwise |
| Weight scaling | Per-output-channel |
| Activation scaling | Dynamic per-token |
| ModelOpt algorithm | FP8_PER_CHANNEL_PER_TOKEN |
| Kernel | CUTLASS FP8 in vLLM-Omni |
“Mixed9” and “Mixed9.25” are parameter-weighted effective precisions. They do not denote scalar 9-bit dtypes.
FL2VA Mixed9
The root checkpoint was selected using BF16-vs-dynamic-FP8 relative MSE.
| Component | Achieved precision | FP8 groups | FP8 parameters | BF16 groups | BF16 parameters |
|---|---|---|---|---|---|
| H3 transformer | 8.997527 bits | 203 | 28,988,080,128 | 63 | 4,129,456,128 |
| Qwen3-VL language encoder | 8.994409 bits | 166 | 21,349,007,360 | 34 | 3,030,384,640 |
FL2VA transformer scope
Kept in BF16:
proj_in,audio_proj_in,context_embedder, both timestep embedding linears,proj_out, andaudio_proj_out.- Attention output projections in transformer blocks 29-48.
- FFN input/gate-up projections in blocks 28, 31, 32, 33, 41, 45, and 46.
- FFN output projections in blocks 5, 6, 8-10, 12-14, 19, 20, and 30-48.
- Biases, normalization parameters, RoPE buffers, and other non-linear state.
Quantized to dynamic FP8:
- All Q/K/V projections and AdaLN linears in transformer blocks 0-49.
- All Linear projections in both token-refiner blocks and
norm_out.linear. - Attention and FFN projections not listed in the BF16 sets above.
Shared Qwen3-VL text encoder scope
Kept in BF16:
- Token embeddings, RMSNorms, rotary state, all non-linear parameters, and the complete Qwen3-VL vision encoder.
- Attention
o_projin language layers 24, 25, 30, 31, 35, 37, 38, 40, and 42-49. - MLP
down_projin language layers 17-19, 21-30, 34, 36, 46, 48, and 49.
Quantized to dynamic FP8:
- All Q/K/V and MLP gate/up projections in language layers 0-49.
- Every attention
o_projand MLPdown_projnot listed above.
The video VAE, audio VAE, tokenizer, processor, embeddings, normalization layers, and vision encoder remain unquantized.
Exact selections and sensitivity scores are stored in:
transformer/transformer_mixed_precision_config.jsontransformer/transformer_sensitivity_ranking.tsvtext_encoder/text_encoder_mixed_precision_config.jsontext_encoder/text_encoder_sensitivity_ranking.tsv
Ref2VA GlobalGrad Mixed9.25
The Ref2VA transformer was independently selected from BF16 using an output-probed global-gradient sensitivity score. This is a custom search inspired by mixed-precision AutoQuant; it is not an NVIDIA ModelOpt AutoQuant export. ModelOpt performs the dynamic FP8 conversion and export.
| Setting | Value |
|---|---|
| Target effective precision | 9.25 bits |
| Achieved effective precision | 9.248862 bits |
| FP8 groups / Linear modules | 212 / 296 |
| FP8 candidate parameters | 27,947,630,592 |
| BF16 groups / Linear modules | 54 / 74 |
| BF16 candidate parameters | 5,169,905,664 |
Ref2VA transformer scope
| Projection family | Dynamic FP8 blocks | BF16 blocks |
|---|---|---|
| Q/K/V | 0, 2-40 | 1, 41-49 |
| Attention output | 0-4, 6-38 | 5, 39-49 |
| FFN input/gate-up | 1-38, 40 | 0, 39, 41-49 |
| FFN output | 0, 2-40 | 1, 41-49 |
| AdaLN Linear | 2-47 | 0-1, 48-49 |
Also quantized to dynamic FP8:
- All Q/K/V, attention-output, and FFN Linear projections in both token-refiner blocks.
norm_out.linear.
Always retained in BF16:
context_embedder,proj_in,audio_proj_in, both timestep embedding linears,proj_out, andaudio_proj_out.- Biases, normalization parameters, RoPE buffers, and all other non-linear state.
Ref2VA reuses the Mixed9 Qwen3-VL text encoder described above. Its VAEs, tokenizer, processor, embeddings, normalization layers, and vision encoder are not quantized. The exact transformer decisions are stored in:
Ref2VA/transformer/transformer_mixed_precision_config.jsonRef2VA/transformer/transformer_sensitivity_ranking.tsv
Similarity samples
These are deterministic short regression samples, not comprehensive perceptual-quality benchmarks.
| Partition | Task | Resolution | Steps | Seed | Video SSIM vs BF16 | Video PSNR | Audio spectral cosine |
|---|---|---|---|---|---|---|---|
| FL2VA Mixed9 | T2VA | 672 x 384 | 10 | 1101 | 0.858496 | 24.7968 dB | not measured |
| Ref2VA Mixed9.25 | Ref2VA | 672 x 384 | 10 | 3101 | 0.758005 | 22.234802 dB | 0.996300151 |
For the Ref2VA sample, FP8 peak GPU memory was 84,842 MiB versus 131,308 MiB for BF16, saving 46,466 MiB (35.39%). The request used the same extracted reference frame/audio and saved BF16 baseline, produced 107 frames, and used a 4-second requested duration. Full machine-readable results are included in:
evaluation/t2va_bf16_similarity.jsonevaluation/ref2va_globalgrad9p25_bf16_similarity.json
vLLM-Omni serving
This checkpoint requires vLLM-Omni with MiniMax-H3 ModelOpt mixed-FP8 loading support.
FL2VA/T2VA:
CUDA_VISIBLE_DEVICES=0 \
vllm-omni serve feizhai123/MiniMax-H3-ModelOpt-Mixed9-Dynamic-FP8 \
--omni \
--host 0.0.0.0 \
--port 8000 \
--trust-remote-code \
--enforce-eager \
--force-cutlass-fp8 \
--enable-cpu-offload \
--stage-init-timeout 1800 \
--init-timeout 2400
Ref2VA:
hf download feizhai123/MiniMax-H3-ModelOpt-Mixed9-Dynamic-FP8 \
--local-dir ./MiniMax-H3-ModelOpt-Mixed9-Dynamic-FP8
CUDA_VISIBLE_DEVICES=0 \
vllm-omni serve ./MiniMax-H3-ModelOpt-Mixed9-Dynamic-FP8/Ref2VA \
--omni \
--host 0.0.0.0 \
--port 8000 \
--trust-remote-code \
--enforce-eager \
--force-cutlass-fp8 \
--enable-cpu-offload \
--stage-init-timeout 1800 \
--init-timeout 2400
Modification notice
Selected H3 transformer and Qwen3-VL language-model Linear weights were modified from the original MiniMax-H3 checkpoints by mixed BF16/FP8 quantization. The VAEs, Qwen3-VL vision encoder, tokenizer, processor, and other explicitly retained parameters remain in their original precision.
Model tree for feizhai123/MiniMax-H3-ModelOpt-Mixed9-Dynamic-FP8
Base model
MiniMaxAI/MiniMax-H3