Methodology
Where every number comes from, how conflicts between sources are resolved, and how often each dataset is refreshed.
WattFit figures come from three source classes — manufacturer specification pages, published independent measurements, and government statistics (EIA) — and every data table states its sources and the date it was last checked. All cost outputs are estimates for informational purposes, not financial advice.
Source classes
| Dataset | Primary source | Cross-check | Refresh cadence |
|---|---|---|---|
| GPU power draw (gaming / idle) | Published reviewer measurements | Vendor rated TBP/TDP | On new GPU releases |
| AIB card dimensions | Board partner spec pages | Review measurements | On new variant releases |
| Case clearance limits | Case manufacturer documentation | Review teardowns | On new case releases |
| US electricity rates | EIA state residential averages | — | At least yearly |
Selection rules
- Measured over rated. When an independent gaming-load measurement exists for a variant, it is the primary figure; the vendor's rated power is shown alongside it.
- Worse case wins on dimensions. If a spec page and a review measurement disagree on length or thickness, the larger value is listed, because fit planning should not rely on the flattering number.
- No single-source synthesis of tables. Data tables are compiled from multiple origins, never copied from another aggregator.
- Reference dates on everything. Each table carries the date its figures were last verified.
Cost calculation basis
Electricity cost estimates use the standard energy formula, published in plain text on each calculator page:
cost = power (W) ÷ 1000 × hours of use × rate (cents/kWh) ÷ 100
Calculators default to your state's average residential rate from the EIA but accept the exact rate from your bill, which is more accurate whenever you have it. Estimates exclude time-of-use pricing, demand charges, and PSU conversion losses unless a calculator states otherwise.
Corrections
If a figure looks wrong, send the page URL and a verifiable source to contact@wattfit.net (details on the contact page). Verified corrections are applied to the dataset and reflected in the table's checked-date.
Disclosure
WattFit has no affiliation with hardware vendors, and no payment influences which products appear or how their figures are reported. Cost outputs are informational estimates, not billing predictions or financial advice.
FAQ
How often is the electricity rate data updated?
State residential rates are refreshed from the EIA's published averages at least once per year, and the reference month is printed next to the table. Rates on your actual bill can differ from the state average, so calculators also accept a custom cents/kWh input.
Why do you use measured power draw instead of TDP?
TDP (or TBP) is a design specification, not a wall measurement. Independent reviews regularly measure gaming draw that sits above or below the rated figure, sometimes by a large margin on factory-overclocked variants. Cost estimates built on measured draw track real bills more closely, so measured figures are used when available and the rated figure is shown alongside for comparison.
Where do the card dimension figures come from?
Primarily from the board partner's official specification page for each variant, cross-checked against published review measurements when available. When the two disagree, the larger figure is listed, since clearance planning should assume the worse case.