The latest RTX 4090 number-porn rumour suggests a GPU with more than 75B transistors

I can't wait for next week to roll around and for us to finally get some concrete numbers about Nvidia's new RTX 40-series graphics cards, because I cannot cope with all the 'holy heck, if this is true…' rumours popping up every single day.

The latest is that the AD102 expected to be powering the RTX 4090 is going to have 165% more transistors than the freakishly beefy GA102 monster that ran the RTX 3090 Ti. Yes, yet another tweaker has come out with some GPU number porn: here's @kopite7kimi claiming that Nvidia's full-fat Lovelace chip is going to be sporting more than 75 billion transistors.

For a full frame of reference, the RTX 3090 Ti's GPU houses 28.3 billion transistors inside its massive 628mm² die, and the Navi 21 chip inside AMD's RX 6950 XT comes in at 26.8 billion in a 520mm² die.

I get that the Lovelace GPU of the RTX 40-series is going to operate with a smaller TSMC N5 (nominally 5nm) production process, as opposed to the Samsung 8nm and TSMC N7 (7nm) lithography of our reference chips above, but still, that's going to be an absolutely enormous graphics processors. 

Surely right at the reticle limits; as big a GPU as it is physically possible to manufacture with today's technology.

Given that the RTX 4090 is expected to offer something in the region of twice the performance of the RTX 3090, you'd expect it to be bigger. But this suggests Nvidia has needed to throw a whole lot more logic at the problem to be able to top its previous biggest GPU to this level.

The transistor number has come from an update to an old tweet of the serial Twitter leaker. Back in April they set up a Twitter poll asking users to guess how many transistors ("xtors") the AD102 GPU would have. The options were 40–50 billion, 50–60 billion, 60–70 billion, and 70–80 billion.

Just over 39% of respondents went for the latter option, which @kopite7kimi has now stated is "the right choice."

Honestly, that's pretty startling. Not that 39% have supposedly got it right, but that Nvidia is really going to create a consumer-facing GPU with such a huge amount of cutting edge silicon inside it. I mean, this is some real brute force, sledgehammer graphics card creation stuff right here.

And sure to be priced to match.

Once again I have to go back to the novelty-size graphics card looks of the RTX 3090 Founders Edition in the system in front of me right now. That card always makes me laugh when I actually take the time to look at it. It's frankly a ridiculous-size graphics card.

Fingers crossed the RTX 4090 looks a whole lot more elegant a device when it finally hits the limelight at Nvidia's GeForce Beyond Special Broadcast on Tuesday September 20.