I Quantized Qwen3.8-27B. “4-Bit” Doesn’t Mean What You Think

I quantized Qwen3.8-27B — and used the process to look at what “4-bit” actually means in practice. Quantization is usually described as if a model simply goes from 16-bit to 8-bit to 4-bit. But real model representations are more complicated than that: different tensors can use different formats, scales, group sizes, packing schemes and precision choices — and two things described as “4-bit” may behave very differently. In this video I use VINDEX3 to inspect, quantize and compare representations of Qwen3.8-27B, looking at what is actually stored, what changes during quantization, and why rep