Model reference · open weights
Qwen3.8-Flash-Next-ROCmFP4-FAST-imatrix is an open-weight language model from agentionai, listed in the AxForge catalogue. AxForge can bring it up on EU-owned hardware for you on request — with the licence handled where one is required.
About
Qwen3.8-Flash-Next ROCmFP4-FAST imatrix GGUF A 180 B model that runs entirely on the GPU of a 128 GB unified-memory box — 87.06 GiB at 4.23 bpw, within 2.5% perplexity of the unquantized model. Sized for the 96 GiB VRAM carve-out of a Strix Halo (Ryzen AI MAX+ 395 / Radeon 8060S). Built and published by Agention. Throughput against context depth, against our closest mainline-compatible quant run on both this fork and stock llama.cpp — numbers and discussion under Holding up at long context. Why this one - Everything stays on the GPU. Not the experts, not the 51.2 B-parameter n-gram table. No host-RAM fallback, no CPU compute in the hot path. - Fast prefill that holds at depth — 423 t/s at 512 tokens, 357 t/s at 8k, still 245 t/s at 32k and 138 t/s at 128k. Prefill is compute-bound and the ROCmFP4 types are cheaper to dequantize. Matters most for long prompts, agentic loops, and anything that re-reads a large context. - Better perplexity than that same mainline tier, by about two standard errors, and better than AesSedai's IQ4XS and IQ3S at 20–30 GB smaller. - Vision included — the model's own tower, at f16, losslessly converted. - Speculative decoding included — the model's own MTP head. Up to 40 tok/s generation observed on a Strix Halo with adaptive drafting; acceptance is content-dependent, so the rate moves with what you are generating. - imatrix-calibrated on 1540 chunks from two corpora, so the low-bit tensors are fitted to real activations rather than assumed. Two layouts, identical weights and identical size (splitting the n-gram table per head is a byte-for-byte restructuring, not a re-quantize): - root — table split per head, fully VRAM-resident. Use this one. - v2/ — table as a single tensor; portable, but needs --ngram-on-disk or host RAM for it, since one tensor that size exceeds what most Vulkan devices accept as a single buffer. Setup Qwen3.8-Flash-Next itself is upstream (ggml-org/llama.cpp#27742). This fork is still needed for the ROCmFPx quant types and the per-head PLE layout as well as the performance improvements listed above. Run --ngram-cache defaults to 256 MiB; raise it for long generations, or throughput drops off over the course of a c
Summarised from the published model card. Read the full card on the HuggingFace links below.
Specifications
| Maker | agentionai |
|---|---|
| Type | Language models |
| Variants | 1 |
| Runs with | gguf |
| Based on | Qwen/Qwen3.8-Flash-Next |
| Released | 2026-08-28 |
| Popularity | 4k downloads / month |
| Likes | 29 |
| Licence | Commercial licence needed |
How it works
Variants
Open weights ship in several sizes and precisions. One page, all the variants — pick the one that fits your GPU. VRAM figures are estimates from model size.
| Variant | Params | Precision | VRAM | Fits 16 GB | Weights |
|---|---|---|---|---|---|
| Qwen3.8-Flash-Next-ROCmFP4-FAST-imatrix-GGUF | — | GGUF | — | — | Weights ↗ |
Using it via the API
Once AxForge deploys qwen3-8-flash-next-rocmfp4-fast-imatrix for you, it answers on the OpenAI-compatible API — the same base URL and keys as every other model. (qwen3-8-flash-next-rocmfp4-fast-imatrix below is illustrative; you get the exact model name on deployment.)
$ curl -sS https://api.axforge.ai/v1/chat/completions \
-H "Authorization: Bearer $AXFORGE_API_KEY" \
-H "Content-Type: application/json" \
-d '{"model":"qwen3-8-flash-next-rocmfp4-fast-imatrix","messages":[{"role":"user","content":"Hello"}]}'
Details
Tags
Licence
The weights are open but its licence needs a commercial agreement for business use. AxForge can arrange that licence and host the model for you — you pay AxForge, we settle with the model’s maker. Ask us for a quote. Read the licence ↗