Updates
The recency layer: material register changes and their decision consequence — each update deep-links into the chapters it updates. Register current through .
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What changed in the register
- 2026-10-14 HPE GB200 NVL72 nominal rack TDP and NVIDIA's full-rack figure for GB300 NVL72; rack power bases, not a cooling-path limit:
132 kW HPE GB200 nominal TDP / up to 142 kW GB300 facility basis→ 132 kW HPE GB200 nominal TDP / up to 142 kW GB300 full rack (NVIDIA) · Ch 5.10 - 2026-10-14 Pegatron's published TDP for each Rubin GPU in its RA4803-72N3 rack; an OEM rating, not measured draw:
~1.8 kW Max Q / 2.3 kW Max P→ 2.3 kW TDP support per Rubin GPU (Pegatron) · Ch 5.1 - 2026-10-14 heating COP reported for most data-center district-heating cases in the 2025 Yuan et al. review:
COP ~2.5–6→ COP ~3.2–5.0 · Ch 5.9 - 2026-10-14 Intel D50DNP primary-loop coolant margin above dew point; one platform's requirement, not a CDU default:
~2 °C above dew point→ ≥2 °C above dew point · Ch 5.12 - 2026-10-14 3M PFAS settlement with US public water systems (final approval Mar 2024); Novec exit by end-2025:
$12.5B→ $10.5-12.5B nominal (2024-2036) · Ch 6.9 - 2026-10-14 ASHRAE liquid classes by max supply water temp (17/27/32/40/45 °C, plus W+); all share a 2 °C lower limit:
W17–W45+→ W17 / W27 / W32 / W40 / W45 / W+ · Ch 5.7 - 2026-10-14 Water-side economizing at one Suwon laboratory building: modeled saving over the five economizer months, and a separate measured 42-day trial:
~42–53% of chiller-plant energy (one site: 42% measured, 52.8% simulated annual)→ 52.8% modeled for Jan–Mar and Nov–Dec; 42.0% measured in a separate 42-day trial · Ch 5.8 - 2026-10-14 Full-flow TCS filtration (follow the rack OEM's requirement); side-stream polishing can be sub-micron, 0.2 µm on Deschutes-design units:
~50-micron→ ~25–50 µm · Ch 5.6 - 2026-10-14 district-heating supply by generation: 2G reference above 100 °C, 3G 80–100 °C; 4G typically 50–70 °C:
70–90 °C→ 2G reference: >100 °C; 3G reference: 80–100 °C · Ch 5.9 - 2026-10-14 GB300 NVL72: Lenovo 135 kW TDP, 155 kW peak, ~90% liquid, ~10% air; NVIDIA RA up to 142 kW:
135 kW TDP; 155 kW peak; up to 142 kW facility design basis; ~90% liquid / ~10% air→ NVIDIA RA up to 142 kW; Lenovo 135 kW TDP, up to 155 kW peak, ~90% liquid / ~10% air; HPE 132 kW nominal, ~155 kW EDPp · Ch 13.10 - 2026-10-14 Vertiv CRV chilled-water in-row units, net sensible kW per unit (CR032 / CR040 / CR050), each at different water conditions:
~30–50 kW→ 27.1 / 46.3 / 53.2 kW per CW unit · Ch 5.2 - 2026-10-14 Rack power: legacy → GB200 NVL72 (~132 kW) → Rubin Ultra Kyber (~600 kW roadmap; NVIDIA H2 2027 target, reported 2028):
132 kW HPE GB200 rack TDP → GB300 135 kW rack TDP / 155 kW peak / up to 142 kW facility basis → VR200 188 kW Max Q / 228 kW Max P / 330 kW facility basis → ~600 kW Rubin Ultra / Kyber roadmap→ 132 kW HPE GB200 rack TDP → GB300 135 kW rack TDP / 155 kW peak / NVIDIA RA up to 142 kW full rack → VR200 188 kW Max Q / 228 kW Max P / 330 kW facility basis → ~600 kW Rubin Ultra / Kyber roadmap · Ch 0.1