AI inference glossary
HardwareTDP

Thermal design power

Also known as TDP, thermal power envelope

In plain English

TDP is the sustained power a chip is designed to draw and shed as heat, the headline wattage on every accelerator spec sheet.

Technical definition

Thermal design power is the maximum sustained power envelope a chip is engineered to operate within, which its cooling system must dissipate continuously.

Engineering details

Modern accelerators run around or above the kilowatt mark per chip, and a full rack system multiplies that into six figures of watts. TDP alone also undersells the true bill: memory, networking, CPUs, power conversion losses, and cooling overhead stack on top, which is why all in power per chip is meaningfully higher than the chip TDP. Datacenter capacity is sold in megawatts, so these envelopes translate directly into how many accelerators a site can host.

Why it matters

Power has become the binding constraint of AI buildout, ahead of capital in many markets. Rising per chip TDP forced the shift to liquid cooling and made performance per watt, not just performance per dollar, a primary axis for comparing silicon generations.

How to read it in InferenceX

The Rubin article specifies a 2300 W TDP production SKU but normalizes facility throughput with all-in utility power. TDP is neither measured inference draw nor total facility power. Its DSX MaxLPS discussion concerns workload-aware power provisioning; the article describes finer-grained PowerX measurements as upcoming rather than treating the displayed curves as measured-power results.