Nvidia RTX 4000 rumor sparks more fears over power usage

An Nvidia graphics card slotted into a test bench with its power cable in the foreground
(Image credit: Future)

Nvidia’s next-gen RTX 4090 flagship could have an eye-opening power usage, at least on the face of it according to the latest rumor – but there’s more to this than meets the eye (as well as some better news further down the RTX 4000 range).

All this comes from a well-established hardware leaker on Twitter, Kopite7kimi, who outlined some purported power details for Nvidia’s Lovelace chips, from AD102 (the flagship) downwards (as spotted by VideoCardz).

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The theory, then is that AD102 GPU will have a ‘power limit’ of 800W, which sounds seriously hefty and worrying (and harks back to earlier days of speculation that Lovelace will be very demanding power-wise).

However, what we must bear in mind here is that this power limit refers to the maximum possible wattage for the GPU, and in reality, the rated TDP will be considerably lower than that for baseline graphics cards. We’ll come back to further chew over what this means in a moment.

The better news is that while AD102 is all the way up there at 800W, Nvidia is supposedly dropping a long way with the GPU that’s purported to be the engine of the RTX 4080, with AD103 sitting at 450W (again, that’s maximum possible wattage). AD104 is then pegged at 400W, and AD106 at 260W.

Kopite7kimi also mentions mobile GPUs, with the AD103 and AD104 mobile chips apparently set to run with a ceiling of 175W, and with AD106 mobile we’re theoretically looking at 140W.

Analysis: Putting things into perspective power-wise

Okay, so before we get too concerned about that whopping 800W figure slapped on the AD102 chip, let’s remember this is just a rumor, and we’ve seen a number of bits of speculation about where Lovelace power usage might end up. But moreover, this doesn’t necessarily mean that the RTX 4090 – which is supposedly the first graphics card Nvidia will launch with the next-generation Lovelace family – will be that much of a monstrous power hog.

As noted above, 800W refers to the maximum possible wattage for the GPU, and the rated TDP will be lower than that, with only more advanced third-party graphics cards which push things much faster with clock speeds (and beefy cooling) getting near to that ceiling (also leaving headroom for overclocking, too).

The other key point with AD102 is that the RTX 4090 is going to have a cut-down version of the GPU, with the grapevine believing it’ll run with 16,384 CUDA Cores (the rumored maximum for the chip is 18,432). There will be other models, most likely an RTX 4090 Ti, and we may even see an RTX Titan for Lovelace above that – and maybe only the Titan will push up to fully exploit that maximum power limit.

When you allow for both of those factors, the RTX 4090 will likely sit a good chunk lower in terms of actual power usage, and it’ll be the full-fat AD102 models – and the speediest top-end cards therein, for that matter – which are going to be pushing their consumption up to get close to that 800W mark (if indeed that’s correct in the first place).

So, don’t start worrying about the RTX 4090 on the power front just yet – the GPU could easily still fall in line with some of the other recent rumors we’ve heard such as 600W for the TDP, although the speculation around a 450W TDP seems shakier in this new light (those TDPs are also assertions from Kopite7kimi, in fact, and RedGamingTech on YouTube in the latter case).

Another interesting point to note here is that the maximum wattage takes a big drop down to 450W for the RTX 4080. Very recently, Kopite7kimi said that the 4080 could nestle at around 420W for its TDP, but this fresh info offers a tentative suggestion that it might pitch a little lower than this (earlier rumors had us forecasting around 400W). And that’d be some better news for the far greater numbers of gamers who are going to want to pick up an RTX 4080, compared to the more niche RTX 4090 with its doubtless exorbitant price tag.

To sum up, let’s not get carried away with any concerns relating to possible power demands yet, although the possibility of necessary PSU upgrades – and indeed better cooling solutions to keep the inside of the PC at a reasonable temperature – clearly remain something of a worry for those looking at a high-end Lovelace GPU.

Darren is a freelancer writing news and features for TechRadar (and occasionally T3) across a broad range of computing topics including CPUs, GPUs, various other hardware, VPNs, antivirus and more. He has written about tech for the best part of three decades, and writes books in his spare time (his debut novel - 'I Know What You Did Last Supper' - was published by Hachette UK in 2013).