[WithinReason]

A 4090 draws 450W unless you unlock the power limit

[Timshel]

Transient might be an issue. GN discuss transients of ~30/40% over the nominal 450w (https://www.youtube.com/watch?v=j9vC9NBL8zo&t=616s).

And with a distributed training you can end-up with "synchronized" transients over all cards :(.

[jagrsw]

I hold an electrical certification in the EU, though I'm not currently practicing.

A quick point: transient surges are usually fine. Both cables and circuit breakers are designed to fail (trip or burn out) under sustained overloads. For example, a 16A Class C circuit breaker might take around an hour to trip with a constant 17A load, but a ~80A load would trip it ~instantly.

PS: Of course, everything is a matter of integration over time (heat dissipation in cables mostly).

[zten]

The workstation equivalent, the RTX 6000 Ada, defaults to 300W. You can get most of the performance of a 4090 by capping the power.