Calculator Inputs
Example Data Table
| Rig type | GPUs | GPU watts | Other watts | Margin | Suggested plan |
|---|---|---|---|---|---|
| Small test rig | 2 | 150 W | 160 W | 20% | One 650 W supply |
| Balanced six GPU rig | 6 | 180 W | 230 W | 20% | Two 850 W supplies |
| Large tuned rig | 8 | 220 W | 300 W | 25% | Two 1300 W supplies |
Formula Used
GPU load = GPU count × watts per GPU × GPU tuning ÷ 100
Base DC load = GPU load + CPU + motherboard + memory + storage + risers + fans + pump + accessories
Planned DC load = base DC load + future reserve watts
Recommended PSU output = planned DC load × (1 + safety margin ÷ 100)
Wall watts = DC load ÷ PSU efficiency decimal
Line amps = planned wall watts ÷ line voltage
Daily kWh = wall watts × run hours per day ÷ 1000
Cost = energy use × price per kWh
How to Use This Calculator
Enter the number of graphics cards and their expected tuned wattage.
Add the CPU, board, memory, storage, riser, fan, pump, and accessory loads.
Use GPU tuning below 100% when cards are undervolted.
Add future reserve watts if you plan to expand the rig.
Set a safety margin for transient load and stable operation.
Enter supply efficiency, line voltage, run hours, and energy price.
Press Calculate to show the result above the form.
Use CSV or PDF download to save a report.
Power Planning for Mining Rigs
A mining rig is a steady electrical load. It can run for many hours without a break. That makes power planning more important than peak wattage alone. A weak supply can crash the rig, heat cables, or waste energy through poor efficiency. This calculator helps you size the supply from the parts that actually draw power.
What the Calculator Checks
The tool totals the graphics cards, processor, board, memory, storage, fans, risers, pumps, and other accessories. It then adds a safety margin. The margin gives the power supply room for startup spikes, aging parts, hot rooms, and future upgrades. The result is a recommended DC output rating, because power supplies are rated by output power.
Efficiency and Wall Power
Power supply efficiency changes the power taken from the wall. A rig that needs 900 watts from the parts may pull more than 900 watts from the outlet. The lost energy becomes heat. Better efficiency lowers heat and cost. The calculator uses your efficiency percentage to estimate wall watts, line current, daily energy use, monthly cost, and yearly cost.
Why Headroom Matters
Running a supply at its limit is not ideal. Fans may spin faster. Voltage regulation may suffer. Cables may become warmer. A miner also has to consider continuous load. Mining is different from short gaming loads. The power draw is persistent. Extra headroom helps the system stay stable when the room gets warm or hash settings change.
Using Multiple Supplies
Large rigs often use more than one supply. This calculator divides the recommended load by the number of supplies. It rounds the suggested size upward. It also reports total capacity and remaining headroom. Keep GPUs and risers on the same supply when possible. That reduces ground and cable issues.
Practical Setup Notes
Use quality cables. Avoid cheap splitters. Check the current rating of each connector. Balance loads across supplies and wall circuits. Compare the calculated amperage with the breaker rating. Keep some spare capacity on the circuit. The calculator gives an engineering estimate. Always follow electrical codes and equipment manuals. For best accuracy, measure tuned GPU wattage with monitoring tools. Update inputs after undervolting, overclocking, driver changes, or adding cards to the frame again.
FAQs
What size power supply do I need for mining?
Add all component wattages, then include reserve and safety margin. The recommended output should be below total power supply capacity. More headroom usually improves stability and reduces stress.
Are power supplies rated by wall power?
No. Most computer power supplies are rated by DC output. Wall power is higher because efficiency losses occur inside the supply and become heat.
Why does efficiency matter?
Efficiency affects wall draw, heat, and power cost. A more efficient supply wastes less energy while delivering the same DC output to the rig components.
Should I use one large supply or two smaller supplies?
Both options can work. Large rigs often use two supplies for connector count and load sharing. Keep each GPU and its riser on the same supply when possible.
How much safety margin is good?
A 20% margin is a common planning value. Higher margins may help with startup spikes, future upgrades, hot environments, and continuous mining loads.
Does undervolting reduce the required supply size?
Yes. Undervolting can reduce GPU wattage. Enter the tuned wattage or use the GPU tuning percent to model the lower load more closely.
Can this calculator check wall circuit limits?
It estimates line current from planned wall watts and voltage. Compare that value with your breaker and wiring limits. Follow local electrical rules.
Why is the energy cost only an estimate?
Actual cost depends on pool settings, coin algorithm, GPU tuning, ambient temperature, supply efficiency curve, uptime, and your real electricity rate.