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PSU Wattage Calculator

Pick your CPU and GPU and we'll tell you the exact power supply wattage your PC needs — with the right efficiency tier and enough headroom for GPU spikes. Stop overpaying for watts you'll never use.

Recommended power supply
750W
80+ Gold · runs at ~55% load at peak. Bare minimum is 500W, but that leaves no headroom.
System draw
410W
CPU
120W
GPU
200W
Solid PSUs at this wattage
MSI MAG A750GL (750W, 80+ Gold, ATX 3.0) ↗
Native 12VHPWR cable — ideal for a 4070-class card.
Corsair RM850e (850W, 80+ Gold, ATX 3.1) ↗
The safe default for high-end single-GPU rigs.

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PSU wattage by graphics card

RTX 5090 PSURTX 5080 PSURTX 5070 Ti PSURTX 5070 PSURTX 5060 Ti PSURTX 5060 PSURTX 4090 PSURTX 4080 PSURTX 4070 Ti PSURTX 4070 Super PSURTX 4070 PSURTX 4060 Ti PSURTX 4060 PSURTX 3090 PSURTX 3080 PSURTX 3070 PSURTX 3060 Ti PSURTX 3060 PSUGTX 1660 Super PSUGTX 1650 PSURX 7900 XTX PSURX 7900 XT PSURX 7800 XT PSURX 7700 XT PSURX 7600 PSURX 9070 XT PSURX 9070 PSURX 6800 XT PSURX 6700 XT PSURX 6600 PSUIntel Arc B580 PSUIntel Arc A770 PSU

PC power supplies, explained

How many watts does my PC need?

Add up the peak draw of your CPU and GPU — that's ~80% of the total — then add roughly 100W for the motherboard, RAM, drives and fans. Size the PSU so that total sits around 50–60% of its rating: it runs at peak efficiency and leaves headroom for GPU spikes. This calculator does it for you.

Is a bigger PSU always better?

Up to a point. A PSU is most efficient at ~50% load, so a little headroom is good — but a 1000W unit in a 350W build just costs more and runs slightly less efficiently. Match the wattage to the build, don't massively overshoot.

What is 80+ Gold and does it matter?

80+ ratings measure efficiency — how much wall power actually reaches your components versus being lost as heat. Gold is the value sweet spot for most builds; Platinum/Titanium cost more for marginal gains. Cheap unrated PSUs are the one place you should never save money.

What is a 12VHPWR / 12V-2x6 connector?

It's the single 16-pin power cable modern high-end Nvidia cards (RTX 4070 Ti and up, most of the 50-series) use instead of multiple 8-pins. Get an ATX 3.0/3.1 PSU with a native 12V-2x6 cable rather than relying on the adapter that ships with the card.