What PSU do you need for an RTX 4090?
Paired with a Core i9-13900K / 14900K, this build draws about 835W at peak (450W GPU + 295W CPU + system). A 1600W unit runs it at ~52% load. Absolute minimum: 1000W.
| GPU RTX 4090 | 450W |
| CPU Core i9-13900K / 14900K | 295W |
| Motherboard + RAM + drives + fans Rest of system | 90W |
| Total peak draw | 835W |
⚡ The RTX 4090 uses a 12V-2x6 (12VHPWR) connector — choose an ATX 3.1 PSU with a native cable.
→ Adjust for your exact buildRecommended power supplies
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FAQ
Is a 1000W PSU enough for an RTX 4090?
It's the bare minimum, but we'd recommend 1600W. This build peaks around 835W, 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 4090?
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.
Does the RTX 4090 need a 12VHPWR cable?
Yes — get an ATX 3.0/3.1 PSU with a native 12V-2x6 connector rather than using the pigtail adapter that ships with the card.