Qwable 27B Chadrock-ROCmFPX-ULTRAQUALITY-7.61BPW is the new quality-first ROCmFPX GGUF for the Unsloth Qwen3.6 27B MTP line. It replaces the older STRIX QUALITY naming and recipe as the default quality build.
The headline is simple: this is the high-quality Strix Halo ROCmFPX build that keeps the speed path alive without accepting the quality drift seen in earlier small mixed-precision experiments. On the fresh card refresh, it landed at 82 on HermesAgent-20, 154/164 on HumanEval+, 25.92 served MTP decode tok/s on a 20KB prompt, and only 0.002420 mean KLD against the BF16 reference.
This is a model/runtime pairing, not a stock upstream GGUF. The files use ROCmFPX tensor types and should be run with a ROCmFPX-aware llama.cpp runner.
Refresh date: 2026-06-29. Hardware: AMD Ryzen AI Max+ 395 / Strix Halo. Served rows used ROCm, one MTP slot, q8_0/q8_0 target KV, f16/f16 draft KV, draft cap 6, b2048/u512, temperature=0, 512 generated tokens, and a deterministic 20KB prompt measuring 3,946 prompt tokens.
Served MTP Speed
Model
BPW
Prompt tok/s
Decode tok/s
Total time
Draft accepted
Note
UltraQuality 7.61 BPW
7.6146
209.84
25.92
38.56 s
437/439 = 99.5%
new default quality build
Superseded STRIX QUALITY
7.37
177.02
8.37
83.49 s
217/1762 = 12.3%
historical row, not recommended
UltraQuality is over 3.0x the served decode speed of the superseded old STRIX QUALITY row in this refresh, while also improving the distribution-quality metrics below.
File Quality
PPL was measured with llama-perplexity, WikiText raw, n_ctx=2048, 32 chunks. KLD was measured with llama-perplexity --kl-divergence, BF16 reference, n_ctx=512, 16 chunks.
Model
PPL
Mean KLD
KLD p99
KLD p99.9
Same-top
UltraQuality 7.61 BPW
6.5212 +/- 0.09323
0.002420 +/- 0.000481
0.019161
0.150872
97.843% +/- 0.227
Superseded STRIX QUALITY
6.5097 +/- 0.09282
0.007113 +/- 0.001182
0.057581
0.308613
96.495% +/- 0.288
The PPL row is intentionally not the final quality judge here. UltraQuality is the model that preserves the BF16 distribution closely enough to be the quality default.
Agent And Coding Validation
HermesAgent-20 and EvalPlus are the behavioral checks that catch failures PPL can miss. UltraQuality was rerun for this card refresh. Historical comparison rows are retained only to show what the new default replaces.
Model
HermesAgent-20
HumanEval base
HumanEval+
Harness failures
UltraQuality 7.61 BPW
82
160/164 = 97.56%
154/164 = 93.90%
0/164
Superseded STRIX QUALITY
78
161/164 = 98.17%
155/164 = 94.51%
0/164
Unsloth Q6 comparison
not rerun in refresh
160/164 = 97.56%
153/164 = 93.29%
0/164
The important result is the combined shape: UltraQuality keeps Q6-class coding behavior, beats the old STRIX QUALITY row on HermesAgent-20, and reduces KLD drift versus the historical quality recipe.
Recipe Notes
UltraQuality is the user-facing name for the ranked leave-32 ROCmFPX recipe from the current tuning pass. The local build artifact was the attention-rank-leave32/Q6K-splice candidate, promoted here under the clean public name:
Qwable 27B Chadrock-ROCmFPX-ULTRAQUALITY-7.61BPW
The older STRIX QUALITY recipe used broad Q6/Q8 promotion and was good enough to show the quality direction, but it had bad served-MTP draft behavior in the refresh. UltraQuality protects the tensors that mattered more surgically, which is why its KLD tail and MTP acceptance recovered at the same time.
Run With ROCmFPX
Build or use a ROCmFPX-aware llama.cpp runner, then launch the default UltraQuality file with the served MTP profile below.
The public names intentionally hide the internal recipe filenames. The internal UltraQuality source artifact was the ranked leave-32/Q6K-splice GGUF from the ROCmFPX tuning run.
Limitations
This is specifically tuned and measured for AMD Strix Halo / Ryzen AI Max+ 395 with ROCm.
Stock upstream llama.cpp is not enough; use a ROCmFPX-aware runner.
The headline speed row is a 20KB served-MTP prompt refresh, not a full long-context sweep.
UMA memory reporting on this platform does not map cleanly to a simple discrete-GPU VRAM number, so this card uses file size and BPW as the public size metrics.
