7 ms·

I really appreciate this analysis and the straightforward top line number 134e6/mm^2. The usual "node" figure is utterly meaningless; an electrical engineer co

I really appreciate this analysis and the straightforward top line number 134e6/mm^2. The usual "node" figure is utterly meaningless; an electrical engineer couldn't care less about "feature" size (whatever that means.) What is the count of discrete components in a given area? There are 40 billion 5nm (the supposed "node" of these chips) squares in a millimeter of area. That's two orders of magnitude more dense than 134 million. The meaningful achievement is how many discrete electrical components are composed into a given area. Not some arbitrary dimension of some cherry picked subset of these components.

moonchild 6y ago
> The meaningful achievement is how many discrete electrical components are composed into a given area. Not some arbitrary dimension of some cherry picked subset of these components. I disagree. The meaningful achievement is how power-efficient, fast, and cheap you can make a given chip. (Secondarily, how small and how durable wrt cosmic rays; but for most purposes these are not super important.) If that follows as a result of many discrete electrical components being packed into a small area, great; but the latter isn't intrinsically interesting.
- topspin 6y ago
  > If that follows Efficiency, performance and cost are strongly related to density. Price less so; that's a function of supply and demand.
  - asdfasgasdgasdg 6y ago
    > Efficiency, performance and cost are strongly related to density. Price less so; that's a function of supply and demand. They are related, of course, but the important stuff can be measured more directly by looking at how well programs work on a given computer. I think it's just a little odd to praise one cherry-picked, arbitrary metric for being less game-able than another cherry-picked, arbitrary metric. Especially when we have metrics to hand that are a lot closer to what real people care about in a computer. I certainly have never shopped for a CPU based on the number of transistors, but I have made purchasing decisions based on things like cinebench and passmark scores, which try to get at what ultimately matters to me (i.e. how many FPS a CPU will drive in the games I play).
    - ummonk 6y ago
      Are you asserting performance benchmarks aren't gameable?
      - asdfasgasdgasdg 6y ago
        No.
    - Someone 6y ago
      That magazines, sites and fans started using density for bragging rights, just as they used to do with MHz, certainly isn’t fully the fault of manufacturers. Manufacturers use “x nm”, yield (a metric correlated with price, but also completely uninteresting for consumers), etc. because they tell chip designers what they need to know. They avoid benchmark scores because they bring the CPU design in the picture as a variable.
    - topspin 6y ago
      It's a story from a site that focuses on fabrication technology and the semiconductor market place. The topic is device density. This is of interest, even if it doesn't interest you.
      - asdfasgasdgasdg 6y ago
        I appreciate that it's of interest to some people. So is the node figure you denigrated in your original post, though.
        topspin 6y ago
        Doubtless. Angelic visitation is interesting to some people. Those and "node" figures have about the same value and credibility.
  - schappim 6y ago
    Exactly this. From the article: “Even if SRAM scaling kept up, the cost per transistor would still have remained flat from N7 to N5.”
- est31 6y ago
  The issue with power efficiency, speed, and price is that it's even harder to measure than transistor density. Furthermore, I think metrics that measure the technological progress of the silicon manufacturing are a useful tool for enriching comparisons of chips. Yes, numbers like cache sizes (or transistor density) aren't what people ultimately need/want, they want speed, but it still helps them compare chips. Improvements of the underlying process alone could lead to improvements of power efficiency, speed, and price.
eightysixfour 6y ago
> The meaningful achievement is how many discrete electrical components are composed into a given area. Is average over an area the meaningful achievement or is the meaningful achievement the smallest individual gate length? Neither are super useful without additional context.
- hinkley 6y ago
  Let's say I made a tiny transistor but to avoid leakage/interference or melting the transistor, I had to surround it by a bunch of empty silicon. There are lots and lots of cases where this could not be called a success. I hesitate to say there are none, because I'm sure some task that is highly sensitive to latency might potentially benefit, but if you build the whole chip that way, it would actually be a regression.
  - eightysixfour 6y ago
    Sure but, despite the extra space around any individual transistor, you're still shoving 49% more transistors into the same overall amount of space. Then everything benefits and no one cares about the node name.
    - hinkley 6y ago
      > you're still shoving 49% more transistors into the same overall amount of space What I fear is that we've hit the point where this is no longer a safe assumption. That we will be having people chase feature size numbers that don't actually result in a proportional increase in chip density. Transistors per square millimeter is closer to a measure we actually care about (speed of light and clock speed) instead of a bench number that doesn't measure anything except perhaps instructions per watt.
      - eightysixfour 6y ago
        What from the article makes you think that's no longer a safe assumption? The 49% gain is exactly what happened going to 5nm. I don't think anyone actually cares about transistors/mm^2 at all, I think what we care about is perf or perf/watt for our specific workloads. I don't care if the chip is built with vacuum tubes if it is fast, efficient (per dollar and watt), and physically fits in the device I want it in.
coherentpony 6y ago
These things aren't _really_ two-dimensional. They're not really three-dimensional either, but they are objects built out of layers of two-dimensional things. When you measure number of transistors per unit area you will inevitably see something more dense than the "number of 5nm square in a millimeter of area". It's the silicon equivalent of measuring one's BMI.
- hinkley 6y ago
  Video games used to call their pseudo-3d display 2.5D, or if they were feeling fancy, isomorphic. There is a little freedom in the Z axis, but not very much. But if speed of light matters to performance, then a chip design that increases the z axis decreases the euclidean distance between any two gates, which should (or at least could) matter to performance, right?
  - coherentpony 6y ago
    Ultimately it depends on the design but you're basically right, yes.
  - Dylan16807 6y ago
    > But if speed of light matters to performance It barely matters. Gate delays and thermal limits outweigh distance by a huge factor. If you need to go further distances then you can wait one cycle and cover a relatively huge length.
    - hinkley 6y ago
      > you can wait one cycle and cover a relatively huge length. At the cost of increasing pipeline depth, right? We've been wrestling with that forever.
      - Dylan16807 6y ago
        I would expect your pipeline steps to be far smaller than this scale. We've been wrestling with the number of pipeline stages vs. the number of transistors in the critical path forever. Not so much physical distance.
hinkley 6y ago
A cycle or two ago I asked this same question. Some people seemed to think that such a number would be gamed, but if that's a valid barrier to entry then we will never accomplish anything again, really. As long as the measure is in mm^2, not mm^3, I think (hope?) that would avoid any perverse incentives against breakthroughs that allow you to add more layers to a chip and still maintain yields.
narrator 6y ago
The funny thing is is this isn't really Apple's achievement. It's TSMC's achievement. It's also Intel's failure in that they failed to get a similar process working on schedule.
- desiarnezjr 6y ago
  Yes, but Qualcomm, Nvidia, AMD and countless others use the same fabs or at least have access to the same fabs. It's Apple's engineering and design.
  - m463 6y ago
    "Apple Books TSMC's Entire 5nm Production Capability" https://www.extremetech.com/computing/315186-apple-books-tsmcs-entire-5nm-production-capability https://www.extremetech.com/computing/315186-apple-books-tsm... so it seems apple paid to get to the front of the line
    - desiarnezjr 6y ago
      And the problem there is? Any one of those companies are all long term TSMC customers and I have no doubt have solid working relationships with them. They would have had similar opportunity to book that fab capacity too.
      - kilburn 6y ago
        The problem is the assertion that "It's Apple's engineering and design". Engineering & design don't buy you the entire world's supply of the best in class fab capacity for some months: money does. It seems to me apple's marketing and product strategy has more to do with bringing in that money than actual engineering and design, contradicting the original assertion.
        dev_tty01 6y ago
        Apple's engineering and design success is a huge part of why they have the resources to likely fund some of the 5 nm fab deployment costs and capacity. Money comes from success which came from great engineering and design coupled with great marketing. Marketing might get you there for a short time, but maintaining that growth and long term high customer satisfaction doesn't come without great engineering and design.
Nokinside 6y ago
> straightforward top line number 134e6/mm^2 Even that number is not so straightforward. Tr/mm^2 = 0.6 * (NAND2 Tr)/mm^2 + 0.4 * (Scan Flip-fop Tr)/mm2
m463 6y ago
"As of 2019, the highest transistor count in any IC chip is Samsung's 1 TB eUFS (3D-stacked) V-NAND flash memory chip, with 2 trillion floating-gate MOSFETs (4 bits per transistor)." [1] How about bit count? (at 4 bits per transistor) [1] https://en.wikipedia.org/wiki/Transistor_count https://en.wikipedia.org/wiki/Transistor_count

moonchild 6y ago

> The meaningful achievement is how many discrete electrical components are composed into a given area. Not some arbitrary dimension of some cherry picked subset of these components. I disagree. The meaningful achievement is how power-efficient, fast, and cheap you can make a given chip. (Secondarily, how small and how durable wrt cosmic rays; but for most purposes these are not super important.) If that follows as a result of many discrete electrical components being packed into a small area, great; but the latter isn't intrinsically interesting.

topspin 6y ago
> If that follows Efficiency, performance and cost are strongly related to density. Price less so; that's a function of supply and demand.
- asdfasgasdgasdg 6y ago
  > Efficiency, performance and cost are strongly related to density. Price less so; that's a function of supply and demand. They are related, of course, but the important stuff can be measured more directly by looking at how well programs work on a given computer. I think it's just a little odd to praise one cherry-picked, arbitrary metric for being less game-able than another cherry-picked, arbitrary metric. Especially when we have metrics to hand that are a lot closer to what real people care about in a computer. I certainly have never shopped for a CPU based on the number of transistors, but I have made purchasing decisions based on things like cinebench and passmark scores, which try to get at what ultimately matters to me (i.e. how many FPS a CPU will drive in the games I play).
  - ummonk 6y ago
    Are you asserting performance benchmarks aren't gameable?
    - asdfasgasdgasdg 6y ago
      No.
  - Someone 6y ago
    That magazines, sites and fans started using density for bragging rights, just as they used to do with MHz, certainly isn’t fully the fault of manufacturers. Manufacturers use “x nm”, yield (a metric correlated with price, but also completely uninteresting for consumers), etc. because they tell chip designers what they need to know. They avoid benchmark scores because they bring the CPU design in the picture as a variable.
  - topspin 6y ago
    It's a story from a site that focuses on fabrication technology and the semiconductor market place. The topic is device density. This is of interest, even if it doesn't interest you.
    - asdfasgasdgasdg 6y ago
      I appreciate that it's of interest to some people. So is the node figure you denigrated in your original post, though.
      - topspin 6y ago
        Doubtless. Angelic visitation is interesting to some people. Those and "node" figures have about the same value and credibility.
- schappim 6y ago
  Exactly this. From the article: “Even if SRAM scaling kept up, the cost per transistor would still have remained flat from N7 to N5.”
est31 6y ago
The issue with power efficiency, speed, and price is that it's even harder to measure than transistor density. Furthermore, I think metrics that measure the technological progress of the silicon manufacturing are a useful tool for enriching comparisons of chips. Yes, numbers like cache sizes (or transistor density) aren't what people ultimately need/want, they want speed, but it still helps them compare chips. Improvements of the underlying process alone could lead to improvements of power efficiency, speed, and price.

eightysixfour 6y ago

> The meaningful achievement is how many discrete electrical components are composed into a given area. Is average over an area the meaningful achievement or is the meaningful achievement the smallest individual gate length? Neither are super useful without additional context.

hinkley 6y ago
Let's say I made a tiny transistor but to avoid leakage/interference or melting the transistor, I had to surround it by a bunch of empty silicon. There are lots and lots of cases where this could not be called a success. I hesitate to say there are none, because I'm sure some task that is highly sensitive to latency might potentially benefit, but if you build the whole chip that way, it would actually be a regression.
- eightysixfour 6y ago
  Sure but, despite the extra space around any individual transistor, you're still shoving 49% more transistors into the same overall amount of space. Then everything benefits and no one cares about the node name.
  - hinkley 6y ago
    > you're still shoving 49% more transistors into the same overall amount of space What I fear is that we've hit the point where this is no longer a safe assumption. That we will be having people chase feature size numbers that don't actually result in a proportional increase in chip density. Transistors per square millimeter is closer to a measure we actually care about (speed of light and clock speed) instead of a bench number that doesn't measure anything except perhaps instructions per watt.
    - eightysixfour 6y ago
      What from the article makes you think that's no longer a safe assumption? The 49% gain is exactly what happened going to 5nm. I don't think anyone actually cares about transistors/mm^2 at all, I think what we care about is perf or perf/watt for our specific workloads. I don't care if the chip is built with vacuum tubes if it is fast, efficient (per dollar and watt), and physically fits in the device I want it in.

coherentpony 6y ago

These things aren't _really_ two-dimensional. They're not really three-dimensional either, but they are objects built out of layers of two-dimensional things. When you measure number of transistors per unit area you will inevitably see something more dense than the "number of 5nm square in a millimeter of area". It's the silicon equivalent of measuring one's BMI.

hinkley 6y ago
Video games used to call their pseudo-3d display 2.5D, or if they were feeling fancy, isomorphic. There is a little freedom in the Z axis, but not very much. But if speed of light matters to performance, then a chip design that increases the z axis decreases the euclidean distance between any two gates, which should (or at least could) matter to performance, right?
- coherentpony 6y ago
  Ultimately it depends on the design but you're basically right, yes.
- Dylan16807 6y ago
  > But if speed of light matters to performance It barely matters. Gate delays and thermal limits outweigh distance by a huge factor. If you need to go further distances then you can wait one cycle and cover a relatively huge length.
  - hinkley 6y ago
    > you can wait one cycle and cover a relatively huge length. At the cost of increasing pipeline depth, right? We've been wrestling with that forever.
    - Dylan16807 6y ago
      I would expect your pipeline steps to be far smaller than this scale. We've been wrestling with the number of pipeline stages vs. the number of transistors in the critical path forever. Not so much physical distance.

hinkley 6y ago

A cycle or two ago I asked this same question. Some people seemed to think that such a number would be gamed, but if that's a valid barrier to entry then we will never accomplish anything again, really. As long as the measure is in mm^2, not mm^3, I think (hope?) that would avoid any perverse incentives against breakthroughs that allow you to add more layers to a chip and still maintain yields.

narrator 6y ago

The funny thing is is this isn't really Apple's achievement. It's TSMC's achievement. It's also Intel's failure in that they failed to get a similar process working on schedule.

desiarnezjr 6y ago
Yes, but Qualcomm, Nvidia, AMD and countless others use the same fabs or at least have access to the same fabs. It's Apple's engineering and design.
- m463 6y ago
  "Apple Books TSMC's Entire 5nm Production Capability" https://www.extremetech.com/computing/315186-apple-books-tsmcs-entire-5nm-production-capability https://www.extremetech.com/computing/315186-apple-books-tsm... so it seems apple paid to get to the front of the line
  - desiarnezjr 6y ago
    And the problem there is? Any one of those companies are all long term TSMC customers and I have no doubt have solid working relationships with them. They would have had similar opportunity to book that fab capacity too.
    - kilburn 6y ago
      The problem is the assertion that "It's Apple's engineering and design". Engineering & design don't buy you the entire world's supply of the best in class fab capacity for some months: money does. It seems to me apple's marketing and product strategy has more to do with bringing in that money than actual engineering and design, contradicting the original assertion.
      - dev_tty01 6y ago
        Apple's engineering and design success is a huge part of why they have the resources to likely fund some of the 5 nm fab deployment costs and capacity. Money comes from success which came from great engineering and design coupled with great marketing. Marketing might get you there for a short time, but maintaining that growth and long term high customer satisfaction doesn't come without great engineering and design.

Nokinside 6y ago

> straightforward top line number 134e6/mm^2 Even that number is not so straightforward. Tr/mm^2 = 0.6 * (NAND2 Tr)/mm^2 + 0.4 * (Scan Flip-fop Tr)/mm2

m463 6y ago

"As of 2019, the highest transistor count in any IC chip is Samsung's 1 TB eUFS (3D-stacked) V-NAND flash memory chip, with 2 trillion floating-gate MOSFETs (4 bits per transistor)." [1] How about bit count? (at 4 bits per transistor) [1] https://en.wikipedia.org/wiki/Transistor_count https://en.wikipedia.org/wiki/Transistor_count