What PSU do you need for an RTX 3090?
The RTX 3090 draws up to about 400W under full load. On its own that only tells half the story — your total system power (and so the PSU you need) depends just as much on your CPU, drives and cooling. This page sizes a supply for the RTX 3090 paired with a Core i9-13900K / 14900K; if your parts differ, the calculator gives your exact number in seconds.
Paired with a Core i9-13900K / 14900K, this build draws about 785W at peak (400W GPU + 295W CPU + system). A 1600W unit runs it at ~49% load. Absolute minimum: 1000W.
| GPU RTX 3090 / 3090 Ti | 400W |
| CPU Core i9-13900K / 14900K | 295W |
| Motherboard + RAM + drives + fans Rest of system | 90W |
| Total peak draw | 785W |
Recommended power supplies
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FAQ
Is a 1000W PSU enough for an RTX 3090?
It's the bare minimum, but we'd recommend 1600W. This build peaks around 785W, and a 1600W unit keeps it near 55% load — the efficiency sweet spot — with headroom for the GPU's transient spikes.
What efficiency rating should I get for an RTX 3090?
80+ Gold or Platinum. It's the best balance of price and efficiency for a build this size. Never pair a good GPU with a cheap unrated PSU.