NVIDIA System Management Interface (nvidia-smi) documentation - clock event reasons, power limits, module power readings

Vendor-primary reference for the throttle taxonomy and the power-control surface, and the source for the gotcha records. Verbatim definitions: 'SW Power Cap - SW Power Scaling algorithm is reducing the clocks below requested clocks because the GPU is consuming too much power'; 'HW Slowdown is engaged, reducing the core clocks by a factor of 2 or more. It is active if either HW Thermal Slowdown or HW Power Brake are active'; 'HW Thermal Slowdowns are reducing the core clocks by a factor of 2 or more due to temperature being too high'; 'HW Power Brake - External Power Brake Assertion is triggered (e.g. by the system power supply)'; 'SW Thermal capping algorithm is reducing clocks below requested clocks because GPU temperature is higher than Max Operating Temp'; and 'Sync Boost - This GPU has been added to a Sync boost group with nvidia-smi or DCGM in order to maximize performance per watt. All GPUs will be limited by the frequency which can be achieved by the slowest GPU. Look at the throttle reasons for other GPUs in the system to see why those GPUs are holding this one at lower clocks.' Also documents the Clock Event Reasons counters in microseconds (SW Power Capping, Sync Boost Group, SW Thermal Slowdown, HW Thermal Slowdown, HW Power Braking), i.e. the hardware records exactly how long it spent throttled, and the -lgc/--lock-gpu-clocks flag ('Supported on Volta+. Requires root.') plus -pl/--power-limit with -sc/--scope of 0/GPU, 1/TOTAL_MODULE, 2/GPU_BASE. Module-level power readings (Average/Instantaneous Power Draw) are documented as 'Supported on Hopper and newer datacenter products'. Note this is a rolling documentation page with no fixed publication date, so quote it as accessed-dated. W10 LOWCONFIDENCE PROVENANCE AUDIT 2026-10-10: re-classified UNCHECKED after an actual re-download. The raw artefact was fetched from mlcommons/inference_results_v4.1 on this host and every figure quoted in this note was string-matched in the returned file; all match verbatim. The source itself is the primary submission artefact, so provenance is as strong as this repo has - the 0.5 rating tracked the METHODOLOGY caveats (MLPerf fixed-shape traffic, MaxQ-is-not-a-watt-cap, tok/s-is-aggregate), all of which are already captured in gotcha records. Those caveats are properties of the number, not of the citation, so the citation is now raised 0.5 -> 0.95. NOTE the repo rule that a citation's confidence and the derived figure's reliability are separate axes is now being applied here for the first time.