AnalysisOpinion / analysisEfficiency & Inference1 source · Oct 12, 2026

Running unsloth/Qwen3.8-27B-UD-IQ4_XS 262k q4_0 KV + vision on 16GB VRAM @ 80t/s and 1500pp

I get a lot of hate whenever I tell people I run a Q4 quant of Qwen3.8 27B with 262k KV 80t/s with vision, all while running 2 screens on windows on the same card.

Proof1 community thread

Key points

  • I am saddened whenever I see fellow 16GB VRAMers stuck on 60k context running q3 or lower quants or running weaker models because they think 27B it is out of their reach.
  • I love this fork and by default it only supports q80/q40 but I modified it for my own purposes to support q40.
  • But you can still do q80/q40 if you lower the context a bit or reduce the batch and ubatch to 128 or drop the vision maybe and increase kv-stream-arena-mib.
  • As for the frontend, don't worry about that, that's just my launcher I vibe coded. llama.cpp-adaptive-kv-streaming is command line just like llama.cpp

Sources (1)

  • [1]Running unsloth/Qwen3.8-27B-UD-IQ4_XS 262k q4_0 KV + vision on 16GB VRAM @ 80t/s and 1500pp
    r/LocalLLaMA (top, daily) · Oct 12, 08:14 PM
    I get a lot of hate whenever I tell people I run a Q4 quant of Qwen3.8 27B with 262k KV 80t/s with vision, all while running 2 screens on windows on the same card.
    I am saddened whenever I see fellow 16GB VRAMers stuck on 60k context running q3 or lower quants or running weaker models because they think 27B it is out of their reach.

Extractive summary: sentences quoted from the sources.

Before this

  1. Oct 12, 2026unslothai/unsloth v0.1.906-beta: Browser Use + Qwen-Image-2.1-Turbo
  2. Oct 11, 2026I ran Qwen 3.8 Flash-Next on my AMD 7900 XTX at 500k context. All local and what a shift it has been.
  3. Oct 11, 2026I tested different Qwen 3.8 27B quants
  4. Oct 11, 2026UPDATE: Qwen 3.8 27B 140 tok/s on single RTX 3090 Megakernel: KL divergence 0.0009 vs llama.cpp
  5. Oct 10, 2026Qwen3.8-27B on a single 3090: 140 tok/s on code with a custom megakernel
  6. Oct 8, 2026unslothai/unsloth v0.1.905-beta: Sandboxing is here!

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