- The card itself draws about 200W under load.
- A complete mid-range system around it lands near 330–380W.
- A 550W unit is enough. A 650W unit is what to buy.
- Nvidia’s own 650W figure assumes a high-end CPU, not a typical one.
How much power does an RTX 4070 use on its own?
About 200W under sustained gaming load. That is the card’s rated board power, and unlike the previous generation, measured draw sits close to the rating rather than well above it. Transient spikes push briefly higher, which matters for power supply choice but not for the average figure.
Two things change this. Factory-overclocked models from board partners typically raise the limit to 215–225W. And a card left at stock in a case with poor airflow will pull its full allowance for longer, because the cooler never gets ahead of the heat.
What does a full system with a 4070 draw?
Add the rest of the build and the picture looks like this for a typical mid-range pairing:
| Component | Under load |
|---|---|
| RTX 4070 | 200W |
| Six or eight-core CPU | 65–105W |
| Motherboard and memory | 45W |
| One NVMe drive | 8W |
| Three case fans | 6W |
| Total | 324–364W |
Pair the same card with a high-core-count processor under a full load on both at once and the figure climbs past 450W. That combination is rare in gaming, where the CPU is usually nowhere near its limit, but it is the case a power supply has to survive.
What size PSU should you actually buy?
A 550W unit from a reputable line will run this build without complaint. A 650W unit costs roughly $15 more and gives you three things: headroom for a GPU upgrade later, quieter operation because the fan spends less time ramped up, and a load point nearer 55% where efficiency peaks.
The wattage number is also the least important part of the decision. A 650W unit from a well-reviewed platform is a better purchase than an 850W unit from an unfamiliar one. Power supplies are the single component whose failure can damage others.
Do you need the new 12VHPWR connector?
The RTX 4070 ships with an adapter in the box and works from standard 8-pin PCIe connectors, so an older power supply is not disqualified. If you are buying a new unit, an ATX 3.x model with a native 12V-2×6 cable removes the adapter and handles transient spikes to spec rather than by margin. Worth having, not worth replacing a working unit for.
Frequently asked
Is 500W enough for an RTX 4070?
With a 65W processor and a quality unit, yes, but with very little margin. It will work and it will be louder under load. There is no good reason to choose it over 650W at current prices.
Will a 4070 bottleneck an older CPU?
At 1440p and above, rarely. At 1080p with a processor from 2019 or earlier, often. The estimator on this site models the CPU as a ceiling, which shows where that line falls for a specific pairing.
How much does undervolting help?
A modest undervolt typically drops sustained draw to roughly 170–180W with no measurable frame-rate loss. It is the single best thermal change available on this card and it takes about ten minutes.
Total draw and a PSU recommendation for your exact parts.
Correction, 18 September 2026: an earlier version gave the board power as 220W, which is the figure for factory-overclocked models rather than reference cards.