The inside of one rack from the container in Fig 7: 72 B300 GPUs as eighteen compute trays of four (9 below and 9 above the mid-rack NVLink switch band, so the NVLink cables stay short), eight power shelves at the base, and one tray — Tray 14 — slid out on its rails with its four GPU cold plates showing. Cold plates capture about 90% of the heat into PG25 at 34 °C in, 44 °C out; a hose pair with dripless quick disconnects ties every tray to the rack manifold, the blue supply and amber return pipes at the rack's right side. The copper riser at the front-left corner is the 54 V DC busbar: at 136 kW it carries about 2,519 A to the shelves, which is why it is a bar and not a cable. Every number comes from one model object, driven by the load slider.