What model? Also, I don't know what "the PrismaAQUA" means, ddg thinks it's a CPAP machine, which seems unlikely to help with inference performance.
Also, 4-bit has measurable intelligence loss. Sometimes worth it, but, at this size models are barely smart enough at 8 or 6.
Qwen3.8-27B-PrismaAQUA-5.5bit-vllm
The output quality is higher. It's held at full precision (not quantized).