DeepSeek V4 Flash 284B (13B active)

User reports DeepSeek V4 Flash MXFP4 at 36.1 t/s decode and 497 t/s prefill served across a Radeon 8060S iGPU and an RTX PRO 6000 Blackwell. Setup is llama.cpp with the rocm-cuda backend on two GPUs, the Strix Halo iGPU plus an external RTX PRO 6000 96 GB, MXFP4 weights (146 GB) fully GPU-resident with no CPU offload and the experts of 18 layers on the iGPU, under Windows. The repo also reports that on Blackwell a CUDA 13.3 build of llama.cpp loses 50-80% of decode past 8192 context: an unnamed 27B model on the RTX PRO 6000 drops from 72 to 35 t/s, while a CUDA 12.8 build of the same commit keeps 74.6 t/s at 8K. gpt-oss-120b runs 52 t/s on the iGPU alone, and Qwen3.8-Flash-Next Q4_K_M across two AMD GPUs gave 21.5-25.8 t/s decode at 4K.