Layer 1 · The numbers that decide
PUE — power usage effectiveness
Total facility power divided by IT power. 1.0 is perfect; every 0.1 above it is overhead you pay for and never compute with.
The number
- What it is
- Total facility power divided by IT power. 1.0 is perfect; every 0.1 above it is overhead you pay for and never compute with.
- Typical values
- 1.4-1.6 air · 1.1-1.2 direct-to-chip · 1.02-1.10 immersion
Verified 2026-09-06.
The catch
PUE says nothing about how much useful work the IT load did. A facility running idle GPUs at PUE 1.1 is efficient and wasteful at the same time. It is a facility metric being widely misused as a performance one.
What this is powering
A GB200 NVL72 rack draws 120–132 kW and a GB300 pushes 135–200 kW, against a 2026 average rack of about 27 kW. The silicon decision and the power decision are the same decision, made eighteen months apart.
Layer 2 — Silicon · GB200 NVL72 · The 150 W inference option