Summary
User reports Qwen3.8-Flash-Next running at 200-300 t/s on a single RTX 5090, entirely in the card's 32 GB with no offloaded experts.
The weights are a 1.66bpw EXL3 quant; cache quantization is used, and the user notes one 32 GB GPU leaves little room for context.
The speed is given only as a range. The user calls the sub-2bpw quant stable, with no reasoning loops.