We built a calibration-aware Q4_K_M quant of Qwen3.5 0.8B that recovers 96.5% of the BF16 gap vs pure llama.cpp Q4_K_M (SpectralQuant)
Summary
A calibration-aware Q4_K_M quantization of Qwen3.5 0.8B using SpectralQuant recovers 96.5% of the BF16 performance gap compared to the standard llama.cpp Q4_K_M quant.
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