CalcuGrid

What PSU do I need for a Core i5-12400F?

550 W to 1000 W, depending on the graphics card beside it. With a GeForce RTX 4070 the answer is 650 W.

Where the watts go — Core i5-12400F with GeForce RTX 4070

Power draw by component for a Core i5-12400F build
Component Power
Core i5-12400F at its ceiling117 W
GeForce RTX 4070 board power200 W
Motherboard25 W
Memory module x26 W
NVMe SSD7 W
Case fan x36 W
Continuous draw361 W

The recommendation of 650 W sits that draw at 56% of the supply's rating. The target is 80%: supplies lose capacity as they age, and a graphics card's millisecond transients have to come from somewhere.

Why the answer is a range

A Core i5-12400F is sold as a 65 W processor and draws 117 W when it boosts. Intel calls the second figure Maximum Turbo Power, and it is what the chip pulls whenever it turbos. Sizing a supply against the 65 W on the box is short by 52 W — 80% — before the graphics card is counted at all.

With a GeForce RTX 4070 the system draws 361 W at full tilt, which calls for 650 W. Across the 34 cards below the answer ranges from 550 W to 1000 W: with this processor it is the graphics card that moves the number, not the other way round.

What the box would have told you

Size a supply against the 65 W on this processor's box and, paired with GeForce RTX 4090, you would buy 700 W. That build draws 611 W at full tilt — 87% of the unit you just bought, with nothing left for ageing or for the card's transients. It needs 800 W.

It happens on 24 of the 34 cards here, by as much as 100 W. On the rest the graphics card is light enough that the undercount does not cross a supply size, which is luck rather than a method.

Supply sized from the Core i5-12400F TDP against what the build needs
Graphics card Sized on TDP Actually needed Short by
RTX 4090700 W800 W+100 W
RTX 3090 Ti700 W800 W+100 W
RTX 5080600 W700 W+100 W
RTX 4080 SUPER550 W650 W+100 W
RTX 4080550 W650 W+100 W

Core i5-12400F with every graphics card

Power supply needed for a Core i5-12400F with each graphics card
Graphics card System draw PSU needed Set by
GeForce RTX 5090736 W1000 WBoth agree
GeForce RTX 4090611 W850 WCard maker
GeForce RTX 3090 Ti611 W850 WCard maker
GeForce RTX 5080521 W850 WCard maker
Radeon RX 7900 XTX516 W800 WCard maker
GeForce RTX 3090511 W750 WCard maker
GeForce RTX 3080 Ti511 W750 WCard maker
GeForce RTX 3080511 W750 WCard maker
GeForce RTX 4080 SUPER481 W750 WCard maker
GeForce RTX 4080481 W750 WCard maker
Radeon RX 7900 XT476 W750 WCard maker
Radeon RX 9070 XT465 W750 WCard maker
GeForce RTX 5070 Ti461 W750 WCard maker
GeForce RTX 4070 Ti SUPER446 W700 WCard maker
GeForce RTX 4070 Ti446 W700 WCard maker
Radeon RX 7800 XT424 W700 WCard maker
Radeon RX 7900 GRE421 W700 WCard maker
Radeon RX 7700 XT406 W700 WCard maker
GeForce RTX 3070 Ti451 W650 WCard maker
GeForce RTX 5070411 W650 WCard maker
GeForce RTX 4070 SUPER381 W650 WCard maker
GeForce RTX 3070381 W650 WCard maker
Radeon RX 9070381 W650 WCard maker
GeForce RTX 4070361 W650 WCard maker
GeForce RTX 3060 Ti361 W600 WCard maker
GeForce RTX 5060 Ti341 W600 WCard maker
GeForce RTX 3060331 W550 WCard maker
GeForce RTX 4060 Ti326 W550 WCard maker
Radeon RX 7600326 W550 WCard maker
Radeon RX 9060 XT321 W550 WCard maker
GeForce RTX 5060306 W550 WCard maker
GeForce RTX 5050291 W550 WCard maker
GeForce RTX 3050291 W550 WCard maker
GeForce RTX 4060276 W550 WCard maker

Frequently asked questions

What PSU do I need for a Core i5-12400F?
It depends entirely on the graphics card: 550 W with the lightest here, 1000 W with the heaviest. Paired with a GeForce RTX 4070 the answer is 650 W.
How many watts does a Core i5-12400F actually draw?
117 W at its ceiling, not the 65 W on the spec sheet. Intel publishes the higher number as Maximum Turbo Power; the lower one is a thermal design target, and the gap between them is 52 W.
Is the 65 W TDP the number to size a PSU against?
No. TDP describes what the cooler has to remove under a sustained load, not what the socket can pull in the moment it boosts. Using it here would leave you 52 W short.
Does a Core i5-12400F need a bigger PSU than its TDP suggests?
Yes — 52 W more, before the graphics card. That is the difference between a supply that copes and one that trips under a load spike.
What happens if I size my PSU from the 65 W TDP?
You would buy a supply that is too small on 24 of the 34 cards here, by as much as 100 W — often a whole size, sometimes two.

A sizing estimate, not a measurement. It adds the processor's power ceiling, the graphics card's rated board power and an itemised allowance for the rest of the system, then leaves headroom so the supply is not running at its limit. Real draw depends on the board's power profile, how far the parts are overclocked, and how a particular graphics card handles transient spikes. Treat a result within 50 W of a supply's rating as a reason to choose the next size up.

Data on this page last verified . How these figures are calculated

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