The Nvidia GeForce RTX 4090 may have an 800W power limit, but a lower TDP by default.

Why is it important: According to the leaks, Nvidia’s successor to Ampere is almost ready and it will be hot and hungry. Codenamed Ada Lovelace, the GeForce RTX 4000 series cards can draw 50-100W more than their predecessors across the board, with flagship models breaking new ground.

Veteran leak kopite7kimi, which hit the Ampere spec weeks ahead of everyone else, updated its Ada Lovelace power limit prediction. It’s important to note that power limits are not the same as TDP or TBP; this is the upper limit, which only comes into play during overclocking. However, they are still a good indicator of power consumption, just overpriced.

To torture our power supplies comes the flagship AD102 with a limit of 800 watts. Going down a level, the desktop AD103 is limited to 450W, the AD104 is limited to 400W, and the AD106 is limited to 260W. In the past, xx106 has been used by entry-level GPUs and xx104 by mid-range GPUs, but Nvidia may be changing that.

As you might expect, leaked laptop power budgets are more modest. Kopite says the mobile versions of the AD103 and AD104 are limited to 175W, while the AD106 is limited to 140W. However, since they are parts of a laptop, there will be plenty of room for manufacturers to customize them anyway.

Back to the numbers, you’re probably still hesitating: 800 watts. This is achievable with a pair of new PCIe 5.0 power connectors, each of which can handle 600W (if the card used 8-pin power connectors, it would need six!). But there are not many power supplies on the market with two such ports and such a large capacity.

Cooling will also be an interesting challenge. But putting aside these practical considerations for a moment, let’s say that an 800W ceiling is unreasonable for a GPU with 18,432 CUDA cores (according to Information from the February hack)?

In a fully unlocked state, the AD102 will consume 0.0434W per CUDA core, which is only marginally more than the 0.0419W per core consumed by the RTX 3090 Ti. As Steve pointed out in our RTX 3090 Ti review, this GPU is a voracious monster, but theoretically the AD102 is just as terrible.

And remember, 800W is a (likely) hard limit, not a TDP. A previous report said that Nvidia was testing a TDP of 600W for the 4090, which would boost GPU efficiency and leave 200W as headroom for overclocking.

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