Work out power consumption of server instantly with clear inputs, formula shown and shareable results.
Server power scales roughly linearly between idle and maximum with utilisation, but idle draw is the striking figure: at 120 W idle against 480 W peak, a server at 45 percent utilisation still spends most of its energy simply being switched on. That poor energy proportionality is the strongest argument for consolidation and for powering down idle capacity.
Server power
average watts = idle + (max - idle) x utilisation; annual kWh = watts x 8766 / 1000; cost = kWh x price
Fans, memory refresh, chipset and power supply conversion losses continue regardless of load. Modern platforms are better but far from proportional.
Yes. A supply is most efficient near half load, so a heavily oversized supply wastes energy. Titanium-rated units hold high efficiency across a wider range.