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I feel like the biggest killer of Moore's Law is how much emphasis has been put on lowering/maintaining power consumption in recent years, similar to airplane p

I feel like the biggest killer of Moore's Law is how much emphasis has been put on lowering/maintaining power consumption in recent years, similar to airplane performance/cost in the 1970s.

ghaff 13y ago
I'm not sure what the alternative would be. Yes, given sufficiently heroic power and cooling measures, Intel's Netburst architecture (P4) could probably have been ramped up to 10GHz or so--I think they demoed prototypes running somewhere in that range at one point. But even if you take water cooling as a given, you still have to start really focusing on power/heat at some point.
exDM69 13y ago
Emphasis on lower power consumption does not "kill Moore's law" or have a negative effect on computing performance. On the contrary, CPU performance has been limited by thermal output and power consumption for at least a decade and improving the power consumption will improve the performance, not the other way. Research and development efforts have been concentrated on !/W (bang per watt) for two reasons, the other one being cooling and power supply (battery consumption) on mobile devices in particular and the other reason is being able to run at higher clocks for longer before thermal throttling kicks in. Power consumption and thermal output are relevant for all kinds of modern computers from smartphones to servers to supercomputers. Power consumption and thermal output are related in an almost linear proportionality, twice the power consumption, twice the thermal output. Since clock frequencies stopped going up some ten years ago, we've had a 5x to 10x increase in single core performance (in addition to multi cores) thanks to increase in power and thermal efficiency and smaller transistors. Concentrating on power consumption keeps Moore's law alive rather than kills it.
rm445 13y ago
Should that matter for Moore's Law as it was defined, for number of transistors on a die? I thought that smaller transistors required less current to operate, so the incentives for lowering power consumption and upping transistor count are aligned.
- brazzy 13y ago
  The problem is that current required isn't going down as fast as transistor size, so more transistors now means more power and more cooling difficulties, or you have to work really hard on stuff like sleep modes.
- Daniel_Newby 13y ago
  Smaller size -> lower capacitance -> lower power consumption during state changes. But smaller size -> larger leakage current -> higher baseline power consumption. For several years we have been at the point where the curves cross and power consumption is minimal. The strategy going forward is to turn off parts of the chip when they are not in use, or to reallocate functional units to other tasks (a la Hyperthreading).
- wmf 13y ago
  Dennard's Laws (which say that smaller transistors use less power) are also ending.
  - kken 13y ago
    This is actually the same as Moores law. Dennard was the one to define scaling law in respect to the physical properties of the transistors.

I feel like the biggest killer of Moore's Law is how much emphasis has been put on lowering/maintaining power consumption in recent years, similar to airplane performance/cost in the 1970s.

ghaff 13y ago

I'm not sure what the alternative would be. Yes, given sufficiently heroic power and cooling measures, Intel's Netburst architecture (P4) could probably have been ramped up to 10GHz or so--I think they demoed prototypes running somewhere in that range at one point. But even if you take water cooling as a given, you still have to start really focusing on power/heat at some point.

exDM69 13y ago

Emphasis on lower power consumption does not "kill Moore's law" or have a negative effect on computing performance. On the contrary, CPU performance has been limited by thermal output and power consumption for at least a decade and improving the power consumption will improve the performance, not the other way. Research and development efforts have been concentrated on !/W (bang per watt) for two reasons, the other one being cooling and power supply (battery consumption) on mobile devices in particular and the other reason is being able to run at higher clocks for longer before thermal throttling kicks in. Power consumption and thermal output are relevant for all kinds of modern computers from smartphones to servers to supercomputers. Power consumption and thermal output are related in an almost linear proportionality, twice the power consumption, twice the thermal output. Since clock frequencies stopped going up some ten years ago, we've had a 5x to 10x increase in single core performance (in addition to multi cores) thanks to increase in power and thermal efficiency and smaller transistors. Concentrating on power consumption keeps Moore's law alive rather than kills it.

rm445 13y ago

Should that matter for Moore's Law as it was defined, for number of transistors on a die? I thought that smaller transistors required less current to operate, so the incentives for lowering power consumption and upping transistor count are aligned.

brazzy 13y ago
The problem is that current required isn't going down as fast as transistor size, so more transistors now means more power and more cooling difficulties, or you have to work really hard on stuff like sleep modes.
Daniel_Newby 13y ago
Smaller size -> lower capacitance -> lower power consumption during state changes. But smaller size -> larger leakage current -> higher baseline power consumption. For several years we have been at the point where the curves cross and power consumption is minimal. The strategy going forward is to turn off parts of the chip when they are not in use, or to reallocate functional units to other tasks (a la Hyperthreading).
wmf 13y ago
Dennard's Laws (which say that smaller transistors use less power) are also ending.
- kken 13y ago
  This is actually the same as Moores law. Dennard was the one to define scaling law in respect to the physical properties of the transistors.