Thermal Budgets of AI Accelerators from First Principles: The Thermodynamic Floor, Present Practice, and the Cost of Moving Data

A first-principles thermal budget for AI accelerators. The Landauer erasure floor at 300 K is compared with the energy per operation of a current flagship accelerator at vendor peak throughput and thermal design power (a gap of about eight orders of magnitude), totalled over a published frontier training run of 3.8e25 operations with its heat-rejection requirement, and decomposed with published per-access energies showing that data movement, not arithmetic, dominates. All numbers are produced by the deposited computation script from published constants and specifications. Model calculations: simulated, not measured.