Rack power density
Beginner
How much electricity one cabinet of computers uses. Almost all of it turns into heat, so it is also how much heat must be removed.
Novice
The electrical power drawn by all the equipment in one rack, usually in kilowatts (kW). Since nearly all of it becomes heat, it is also the heat the cooling system must remove from that rack.
Expert
Quoted as design (provisioned) or measured power per rack. Typical enterprise racks run under 10 kW; liquid-cooled AI racks run 100–140 kW, with designs aimed at several hundred kW to 1 MW. It sets busbar current, coolant flow, floor loading and the size of every upstream electrical block.
Explained in Power and cooling (Systems).
See also: PUE (power usage effectiveness), Direct-to-chip liquid cooling (cold plates).