6 ms·

The fabs propped up the corpse of Moore's Law by throwing mountains of cash at expanding transistors into the third dimension: finFET, GAA, CFET, etc. That ha

The fabs propped up the corpse of Moore's Law by throwing mountains of cash at expanding transistors into the third dimension: finFET, GAA, CFET, etc. That has kept the party going a little while longer than it would have lasted but it's a one-time deal since are no more dimensions to expand into.

brookst 2y ago
…but that’s how it’s always worked. Moore’a law is dead, we’re at the limit of everything, oh hey, Moore’s lawn limps by again because someone did something clever.
- light_hue_1 2y ago
  That's never how it worked. Moore's law was never dead. People are just endlessly confused about what Moore's law is. What ended was Dennard scaling around 2006. Roughly that frequency would keep going up as feature size went down. But because so many people are confused about what is what, you see a crappy muddled message. Moore's law has been going strong. It must end eventually, current predictions are that it will be in a decade or two.
  - perching_aix 2y ago
    It's starting to get a bit old that whenever I see Moore's law mentioned, I'll usually also run into a spiel about how people have the wrong idea about what it actually refers to, and that it's holding up just fine. This is despite the gen-on-gen and year-on-year performance improvements of computer hardware very clearly tapering off in recent memory. Maybe debating what always-somehow-wrong law to cite should not be the focus? Like it's very clear to me that being technically correct about what Moore's law or the Dennard scaling refers to is leaps and bounds less important than the actual, practical computing performance trends that have been observable in the market.
    - sitkack 2y ago
      It is ultimately a market effect, the technical specifics are not really important and are even conflated by industry insiders. See my sibling comment.
    - Kon5ole 2y ago
      What we see in the market is caused by software bloat. Chips are gaining performance faster than ever in absolute terms. I think Moore’s law should be avoided altogether when discussing progress in this area, because it’s hard to understand the effects of doubling intuitively. Rice grains on chessboards and all that. One might think ”Moore’s law is slowing down” means progress was faster before and slower now, when it is in fact completely opposite. If you consider the 20 years between the intel 286 and the pentium 3, transistor count went from about 150 thousand to 10 million. Today (using the ryzen 5950 and 7950 as examples), we got 5 Billion more transistors in just 2 years. So in 2 years we added 500 times more transistors to our cpus than the first 20 years of “prime Moore’s law” did. This enormous acceleration of progress is increasingly unnoticed due to even faster increases in software bloat, and the fact that most users aren’t doing things with their computers where they can notice any improvements in performance.
      - perching_aix 2y ago
        > Chips are gaining performance faster than ever in absolute terms. But this is not what I as a consumer end up seeing at all. Consider the RTX 5090. Gen-on-gen (so, compared to the 4090), for 20-30% more money, using 20-30% more power, you get 20-30% more raster performance. Meaning the generational improvement is 0, software nonwithstanding. > If you consider the 20 years between the intel 286 and the pentium 3, transistor count went from about 150 thousand to 10 million. Today (using the ryzen 5950 and 7950 as examples), we got 5 Billion more transistors in just 2 years. Why would you bring absolute values into comparison with a relative value? Why compare the 286 and the P3 and span 20 years when you can match the 2 year timespan of your Ryzen comparison, and pit the P2 ('97) against the P3 ('99) instead? Mind you, that would reveal a generational improvement of 7.5M -> 28M transistors, a relative difference of +273%! Those Ryzens went from 8.3B to 13.2B, a +59% difference. But even this is misleading, because we're not considering die area or any other parameter.
  - wtallis 2y ago
    Also, chip fabs keep getting more expensive and taping out a chip design for those new fabs keeps getting more expensive. That makes today's semiconductor industry work quite differently from how things worked 30 years ago and means some segments see reduced or delayed benefits from the continued progression of Moore's Law. See eg. the surprisingly long-lasting commercial relevance of 28nm, 14nm, and 7nm nodes, all of which were used in leading products like desktop GPUs and CPUs for more years than Moore's Law would lead you to expect.
  - sitkack 2y ago
    Moore's law ends when the whole universe is a computer (which it already is). https://hasler.ece.gatech.edu/Published_papers/Technology_overview/gordon_moore_1965_article.pdf https://hasler.ece.gatech.edu/Published_papers/Technology_ov... Some view it as a doubling every 18 months, or a cost per transistor (this has gone up with the smallest nodes). It is roughly an exponential curve in the number of transistors we can use to make a "thing" with. It is both a capability (can we make things of a certain number of transistors) and is it economically viable to build things of that size. You could stay at the current node size and halve the cost of that wafer every 18 months and you would still be on the same curve. But it is easier in a our economic system to decrease the node size, keeping the rest of the fixed wafer costs the same and get 2x or 4x the density on the same lines. If I get nerd sniped, I'd find the two video presentations one by Krste and another by Jim Keller where they unambiguously explain Dennard Scaling and Moore's Law in a way that is congruent with what I just said.
    - eru 2y ago
      > Moore's law ends when the whole universe is a computer (which it already is). I find "Moore's Second Law" interesting. At least the version I'm familiar with says that the cost of a semiconductor chip fabrication plant doubles every four years. See https://en.wikipedia.org/wiki/Moore%27s_second_law https://en.wikipedia.org/wiki/Moore%27s_second_law It's interesting to contrast that trajectory with global GDP. At some point, either global economic growth has to accelerate dramatically to even produce one fab; or we have to leave the 'globe', ie we go into space (but that's still universal GDP exploding), or that law has to break down. It would be exceedingly funny (to me), if the one of the first two possibilities held true, and would accurately predict either an AI singularity or some Golden space age.
  - DrNosferatu 2y ago
    Moore’s will only end when we have practical optical computing, as it fills a critical technological niche. It’s not impossible, but think I think quantum computing will only become practical later than optical.
- ForOldHack 2y ago
  This is the kind of comment that will keep me laughing for weeks. Moore's lawn is in fact dead. We need to go back to calling what Moore said as his observational insight.
WXLCKNO 2y ago
Depends, there could be 11 dimensions to expand into.
- skissane 2y ago
  Assuming those extra dimensions really exist (it is unproven), I think we are centuries or even millennia away from being able to make technological use of them-if we ever will be at all
- relaxing 2y ago
  Expand into the time dimension, evaluate infinite execution paths by reversing the pipeline, rerunning, and storing the results in a future accumulator.
  - ForOldHack 2y ago
    You give a whole new meaning to branch prediction. I knew you were going there, and I still did not avoid the brain twang.
acchow 2y ago
> since are no more dimensions to expand into. Quantum computing is next, right?
- adastra22 2y ago
  That’s not how quantum computing works.
  - eru 2y ago
    To elaborate: Apart from the very niche application of factoring integers into prime numbers, there's scarcely any application know where quantum computers would even theoretically outperform classical computers. And even integer factoring is only remotely useful, until people completely switch away from cryptography that's relies on it. The one useful application of quantum computing that I know of is: simulating quantum systems. That's less useless than it sounds: a quantum computer can simulate not just itself (trivially), but also other quantum systems. In any case, the real world use case for that is for accelerating progress in material science, not something you nor me would use everyday.
    - adastra22 2y ago
      This isn’t an elaboration on anything I said. Quantum computers are immensely useful across a whole slew of domains. Not just cryptanalysis, but also secure encryption links, chemistry simulations, weather predictions, machine learning, search, finance, logistics, classical simulations (e.g. fluid flow) and basically anywhere you have linear algebra or NP problems.
      - eru 2y ago
        Do you have any sources that give good evidence that quantum computers are useful for 'weather predictions, machine learning, search, finance, logistics, classical simulations (e.g. fluid flow) and basically anywhere you have linear algebra or NP problems'? I'm basing my skepticism mostly on the likes of Scoot Aaronson. I can believe that quantum computers might be useful for chemistry simulations (Quantum computers aren't really useful for encryption. But you could theoretically use them. They just don't really give you any advantage over running a quantum resistant algorithm on a classic computer.) I'm especially doubtful that quantum computer would be useful for arbitrary NP problems or even arbitrary linear algebra problems.
dehrmann 2y ago
> into the third dimension Does this actually work? At some point, and this is been the case for a while, you're limited by thermals. You can't stack more layers without adding more cooling.
- magicalhippo 2y ago
  He's talking about how they've moved from planar transistors, where layers are just deposited on top of each other, to transisors with increasingly complex 3D structures[1] such as FinFET and Gate-All-Around, the latter having multiple nanowires passing through the gate like an ordered marble cake[2]. [1]: https://www.asml.com/en/news/stories/2022/what-is-a-gate-all-around-transistor https://www.asml.com/en/news/stories/2022/what-is-a-gate-all... [2]: https://anysilicon.com/the-ultimate-guide-to-gate-all-around-gaa/ https://anysilicon.com/the-ultimate-guide-to-gate-all-around...
  - ForOldHack 2y ago
    There are also cooling and conduction paths taken into account. It was discussed in the design of the xeon version of the i9. Which had me consider clocking down the performance core communication while throttling up the performance cores. Your sources are excellent. ( Thank you so much for the links. )
- eru 2y ago
  Moore's law doesn't say anything about you having to power all your transistors for them to count. I'm only half-joking: the brain gets a lot of its energy efficiency out of most of its parts not working all that hard most of the time; and we are seeing some glimpses of that in mobile processors, too.

brookst 2y ago

…but that’s how it’s always worked. Moore’a law is dead, we’re at the limit of everything, oh hey, Moore’s lawn limps by again because someone did something clever.

light_hue_1 2y ago
That's never how it worked. Moore's law was never dead. People are just endlessly confused about what Moore's law is. What ended was Dennard scaling around 2006. Roughly that frequency would keep going up as feature size went down. But because so many people are confused about what is what, you see a crappy muddled message. Moore's law has been going strong. It must end eventually, current predictions are that it will be in a decade or two.
- perching_aix 2y ago
  It's starting to get a bit old that whenever I see Moore's law mentioned, I'll usually also run into a spiel about how people have the wrong idea about what it actually refers to, and that it's holding up just fine. This is despite the gen-on-gen and year-on-year performance improvements of computer hardware very clearly tapering off in recent memory. Maybe debating what always-somehow-wrong law to cite should not be the focus? Like it's very clear to me that being technically correct about what Moore's law or the Dennard scaling refers to is leaps and bounds less important than the actual, practical computing performance trends that have been observable in the market.
  - sitkack 2y ago
    It is ultimately a market effect, the technical specifics are not really important and are even conflated by industry insiders. See my sibling comment.
  - Kon5ole 2y ago
    What we see in the market is caused by software bloat. Chips are gaining performance faster than ever in absolute terms. I think Moore’s law should be avoided altogether when discussing progress in this area, because it’s hard to understand the effects of doubling intuitively. Rice grains on chessboards and all that. One might think ”Moore’s law is slowing down” means progress was faster before and slower now, when it is in fact completely opposite. If you consider the 20 years between the intel 286 and the pentium 3, transistor count went from about 150 thousand to 10 million. Today (using the ryzen 5950 and 7950 as examples), we got 5 Billion more transistors in just 2 years. So in 2 years we added 500 times more transistors to our cpus than the first 20 years of “prime Moore’s law” did. This enormous acceleration of progress is increasingly unnoticed due to even faster increases in software bloat, and the fact that most users aren’t doing things with their computers where they can notice any improvements in performance.
    - perching_aix 2y ago
      > Chips are gaining performance faster than ever in absolute terms. But this is not what I as a consumer end up seeing at all. Consider the RTX 5090. Gen-on-gen (so, compared to the 4090), for 20-30% more money, using 20-30% more power, you get 20-30% more raster performance. Meaning the generational improvement is 0, software nonwithstanding. > If you consider the 20 years between the intel 286 and the pentium 3, transistor count went from about 150 thousand to 10 million. Today (using the ryzen 5950 and 7950 as examples), we got 5 Billion more transistors in just 2 years. Why would you bring absolute values into comparison with a relative value? Why compare the 286 and the P3 and span 20 years when you can match the 2 year timespan of your Ryzen comparison, and pit the P2 ('97) against the P3 ('99) instead? Mind you, that would reveal a generational improvement of 7.5M -> 28M transistors, a relative difference of +273%! Those Ryzens went from 8.3B to 13.2B, a +59% difference. But even this is misleading, because we're not considering die area or any other parameter.
- wtallis 2y ago
  Also, chip fabs keep getting more expensive and taping out a chip design for those new fabs keeps getting more expensive. That makes today's semiconductor industry work quite differently from how things worked 30 years ago and means some segments see reduced or delayed benefits from the continued progression of Moore's Law. See eg. the surprisingly long-lasting commercial relevance of 28nm, 14nm, and 7nm nodes, all of which were used in leading products like desktop GPUs and CPUs for more years than Moore's Law would lead you to expect.
- sitkack 2y ago
  Moore's law ends when the whole universe is a computer (which it already is). https://hasler.ece.gatech.edu/Published_papers/Technology_overview/gordon_moore_1965_article.pdf https://hasler.ece.gatech.edu/Published_papers/Technology_ov... Some view it as a doubling every 18 months, or a cost per transistor (this has gone up with the smallest nodes). It is roughly an exponential curve in the number of transistors we can use to make a "thing" with. It is both a capability (can we make things of a certain number of transistors) and is it economically viable to build things of that size. You could stay at the current node size and halve the cost of that wafer every 18 months and you would still be on the same curve. But it is easier in a our economic system to decrease the node size, keeping the rest of the fixed wafer costs the same and get 2x or 4x the density on the same lines. If I get nerd sniped, I'd find the two video presentations one by Krste and another by Jim Keller where they unambiguously explain Dennard Scaling and Moore's Law in a way that is congruent with what I just said.
  - eru 2y ago
    > Moore's law ends when the whole universe is a computer (which it already is). I find "Moore's Second Law" interesting. At least the version I'm familiar with says that the cost of a semiconductor chip fabrication plant doubles every four years. See https://en.wikipedia.org/wiki/Moore%27s_second_law https://en.wikipedia.org/wiki/Moore%27s_second_law It's interesting to contrast that trajectory with global GDP. At some point, either global economic growth has to accelerate dramatically to even produce one fab; or we have to leave the 'globe', ie we go into space (but that's still universal GDP exploding), or that law has to break down. It would be exceedingly funny (to me), if the one of the first two possibilities held true, and would accurately predict either an AI singularity or some Golden space age.
- DrNosferatu 2y ago
  Moore’s will only end when we have practical optical computing, as it fills a critical technological niche. It’s not impossible, but think I think quantum computing will only become practical later than optical.
ForOldHack 2y ago
This is the kind of comment that will keep me laughing for weeks. Moore's lawn is in fact dead. We need to go back to calling what Moore said as his observational insight.

WXLCKNO 2y ago

Depends, there could be 11 dimensions to expand into.

skissane 2y ago
Assuming those extra dimensions really exist (it is unproven), I think we are centuries or even millennia away from being able to make technological use of them-if we ever will be at all
relaxing 2y ago
Expand into the time dimension, evaluate infinite execution paths by reversing the pipeline, rerunning, and storing the results in a future accumulator.
- ForOldHack 2y ago
  You give a whole new meaning to branch prediction. I knew you were going there, and I still did not avoid the brain twang.

acchow 2y ago

> since are no more dimensions to expand into. Quantum computing is next, right?

adastra22 2y ago
That’s not how quantum computing works.
- eru 2y ago
  To elaborate: Apart from the very niche application of factoring integers into prime numbers, there's scarcely any application know where quantum computers would even theoretically outperform classical computers. And even integer factoring is only remotely useful, until people completely switch away from cryptography that's relies on it. The one useful application of quantum computing that I know of is: simulating quantum systems. That's less useless than it sounds: a quantum computer can simulate not just itself (trivially), but also other quantum systems. In any case, the real world use case for that is for accelerating progress in material science, not something you nor me would use everyday.
  - adastra22 2y ago
    This isn’t an elaboration on anything I said. Quantum computers are immensely useful across a whole slew of domains. Not just cryptanalysis, but also secure encryption links, chemistry simulations, weather predictions, machine learning, search, finance, logistics, classical simulations (e.g. fluid flow) and basically anywhere you have linear algebra or NP problems.
    - eru 2y ago
      Do you have any sources that give good evidence that quantum computers are useful for 'weather predictions, machine learning, search, finance, logistics, classical simulations (e.g. fluid flow) and basically anywhere you have linear algebra or NP problems'? I'm basing my skepticism mostly on the likes of Scoot Aaronson. I can believe that quantum computers might be useful for chemistry simulations (Quantum computers aren't really useful for encryption. But you could theoretically use them. They just don't really give you any advantage over running a quantum resistant algorithm on a classic computer.) I'm especially doubtful that quantum computer would be useful for arbitrary NP problems or even arbitrary linear algebra problems.

dehrmann 2y ago

> into the third dimension Does this actually work? At some point, and this is been the case for a while, you're limited by thermals. You can't stack more layers without adding more cooling.

magicalhippo 2y ago
He's talking about how they've moved from planar transistors, where layers are just deposited on top of each other, to transisors with increasingly complex 3D structures[1] such as FinFET and Gate-All-Around, the latter having multiple nanowires passing through the gate like an ordered marble cake[2]. [1]: https://www.asml.com/en/news/stories/2022/what-is-a-gate-all-around-transistor https://www.asml.com/en/news/stories/2022/what-is-a-gate-all... [2]: https://anysilicon.com/the-ultimate-guide-to-gate-all-around-gaa/ https://anysilicon.com/the-ultimate-guide-to-gate-all-around...
- ForOldHack 2y ago
  There are also cooling and conduction paths taken into account. It was discussed in the design of the xeon version of the i9. Which had me consider clocking down the performance core communication while throttling up the performance cores. Your sources are excellent. ( Thank you so much for the links. )
eru 2y ago
Moore's law doesn't say anything about you having to power all your transistors for them to count. I'm only half-joking: the brain gets a lot of its energy efficiency out of most of its parts not working all that hard most of the time; and we are seeing some glimpses of that in mobile processors, too.