Qwen3.6-Plus throughput drops after idle

Likely a GPU driver or power-state bug, not a model or context-window problem. The reboot-only recovery pattern is the strongest clue that the runtime or Radeon stack is getting stuck in a bad state.

• –The user says GPU temperature stays around 40C, which makes thermal throttling an unlikely explanation.
• –Context size changes from 32K down to 4K do not fix it, so this does not look like a simple memory-pressure issue.
• –Similar 7900XTX reports in the wild point to idle-power, clock-states, and driver regressions that only reset cleanly after reboot.
• –For local LLM users on AMD hardware, the next variables to isolate are driver version, backend/runtime changes, and any Windows power-management behavior.