Measure your miner's real power draw

Nominal power is the manufacturer's rating at reference conditions. Wall draw — what the socket delivers — adds PSU conversion losses (3–8%), higher clocks, hot ambients, and fan behavior. A '3,000 W' ASIC commonly measures 2,950–3,250 W; a GPU rig's real draw varies with the memory timings of its current algorithm. Only the wall number appears on your invoice.

• Plug-in power meter ($15–25): fine for rigs under its rating; read W now and cumulative kWh over a day.
• Smart PDU per outlet: the professional version — per-device logging, alerts, remote switching.
• Clamp meter / sub-meter for wired 240 V circuits: electrician territory, same principle.
• Whole-home monitoring: subtract baseline with the rig off — least precise, zero extra hardware.

Final check: your meter says 70 kWh/week for the rig; the bill went up ~$7.40/week at $0.105 effective. If the numbers do not close, something else changed (cooling season, another appliance, a tariff line) — find it before trusting the model. This reconcile habit scales from one rig to a site.

Project hardware sections record measured wall draws from fleet tests where available — the same discipline this lesson teaches.