Move Over Moore's Law, Make Way For Huang's Law (ieee.org)

Tekla Perry writes: Are graphics processors a law unto themselves? Nvidia's Jensen Huang says a 25-times speedup over five years is evidence that they are. He calls this the 'supercharged law,' and says it's time to start counting advances on multiple fronts, including architecture, interconnects, memory technology, and algorithms, not just circuits on a chip.

Comments

Re:Circuits on a chip?

[Jonathan C. Patschke]

Moore's Law is an economic one, not a strictly a technological one. Although, keeping it going depends on semiconductor processes getting finer.

The costs per nanoacre more-or-less follow a predictable curve relative to how bleeding-edge a process is required to fabricate a chip. If you need a really old process, availability will be low, so demand will push the costs up. If you're using the latest, availability is low and yields will initially be low, so the costs are way up. Everything in-between is pretty cheap because demand tends to go towards newer stuff, and the fabrication plant for those middle-aged processes has already started depreciating-out.

If you're trying to be an industry leader, you're targeting the newest processes, so you have the highest expenses. As a result, you want to keep your chip small because costs scale with semiconductor area (N chips per wafer, X dollars per wafer, etc.).

However, there's a lower bound on that. If you've got a chip with over a thousand pins, like a high-end microprocessor, the chip has to be physically large enough to have that many bumps to wire out to pins. Also, there's the case of heat dissipation to consider. A teeny-tiny part that draws a lot of current may shatter or desolder itself if there's not enough surface area to mate with the thermal solution.

So, you want to be small, but there's a lower bound to that. That implies wasted space on the die, which you're going to pay for, anyway. What to do with it?

Add a core! Make the pipelines deeper! More cache! Add some multimedia accelerators. Add an FPGA! Add some other dedicated-function unit! Then present it as a bullet-point for selling more of your part versus your competitor.

Ergo, Moore's Law.