Ok I think I do know the answer but I never learned it, so I want to learn it today. It’s been about 1 year now we can reliably make 3nm chips, which is impressive on a scale of size. But why is is better? My theory is simply: We can make a product the same size but add more on it because it’s smaller, making it stronger and faster for more complex operations. Which would mean it’s not the chip that’s impressive on its own, just the size of it.
Or there is something else, and I’d love to get the full explanation and understand chips better
Well, for a start, those 3nm are supposed to represent the feature size, not the transistor size. The feature size is like the resolution of an image (in fact, it is very very like), so as you reduce it, you can get more and more detailed things, but those things do not necessarily reduce in size. Thus you don’t necessarily get more transistors from a finer process.
But then, the sizes you read about right now are not real feature sizes either. They are calculated by a complex algorithm that takes into account everything, from the cost of the factories to the chip’s power dissipation, and only terminates on the computers of the marketing department. You can’t expect to just read them and learn something useful.