RTX 5090, just because it dual boots as a gaming rig. I have a llama server usually with `gemma4:31b` or `qwen3.6:27b` that powers my own automation / orchestration harness.

If I can go back in time, I would probably buy a more AI dedicated machine but I also don't regret finally being able to play Cyberpunk in 4k with great FPS and overkill mods.