More Cores, but where's the Elegance?

Architecturally, the two individual die that make up Kentsfield are treated as one. This distinction matters especially when you look at power consumption of the new processor. In the event that only one of the two die is being used, the other cannot simply power down; instead it has to run at the same voltage and frequency of the other active die. Within each die, the two cores have to run at the same frequency and voltage as well, so there's not really much flexibility in operation. The end result is that while Kentsfield doesn't use too much more power than Conroe when running four CPU intensive threads simultaneously given the additional work it is doing, when only running two threads, Kentsfield is quite wasteful with its power consumption.

A more efficient solution would be to allow each core to operate at its own frequency, and an even better implementation would require independent power planes per core - allowing for different voltages depending on load. As simple as these two options are to write, they are unfortunately far more difficult to implement. AMD has already announced that its Barcelona quad-core CPUs will support independent clock speeds per core, but not independent voltages.


AMD's Barcelona core, due out in Q2 '07, will have support for independent clocks per core but all sharing the same voltage

Index Using a Quad Core System
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  • PrinceGaz - Thursday, November 2, 2006 - link

    What do you mean it is "a insanely round-about way of measuring power draw"? Can you come up with a better one that doesn't involve cutting tracks on mobos to read the current being passed through them? Or a method which would work equally well with very soon to be released G80 graphics-core which is reputed to dissipate rather a lot of heat (clamp the water-block on that G80 and we'll soon see how much heat it really puts out).

    If you can come up with a simpler and better method of determining the power usage of CPUs and other devices, feel free to divulge the details here because their current method of measuring at the AC power-outlet is woefully inadequate, and I think a water-block heat-transfer system is not only a simple but quite accurate way of measuring power use, but one that can be applied to both CPUs and GPUs.
  • autoboy - Thursday, November 2, 2006 - link

    Wow, all you guys have really weird methods of measuring power draw. Nearly all the power for modern processors comes through the 12V Aux power connector. You can measure the current and voltage here and you will get the power consumption of the processor. However, the efficiency of the VRM can skew the results slightly.
  • Gigahertz19 - Thursday, November 2, 2006 - link

    quote:

    It's tough to tell a Kentsfield apart from a Conroe; although it sounds like a lot, 582 million transistors don't really feel any heavier than only 291 million (and it won't even sound like a lot after another week).


    Ah I like the little hint on the transitor count for Nividia's G80 when they release next week. Can't wait till Nvidia's G80 is released and we get some benchies :)
  • fikimiki - Thursday, November 2, 2006 - link

    Looking at pure encoding performance we can expect only 40-50% increase.
    It is very,very bad.
    Why don't you compare this CPU with Dual-Core Opteron platform?
    Without better cache management this CPU is only for benchmarks same as 4x4 it's with crazy pricing.
  • defter - Thursday, November 2, 2006 - link

    quote:

    Why don't you compare this CPU with Dual-Core Opteron platform?


    Why compare cheaper single-socket platform with more expensive dual-socket platform?

    quote:

    Without better cache management this CPU is only for benchmarks same as 4x4 it's with crazy pricing.


    Are you kidding? Kentsfield PC will be cheaper than 4x4 PC, if Kentsfield will achieve same level of performance, then it will have better price/performance ratio.
  • lopri - Thursday, November 2, 2006 - link

    Damn.. I can't get over how gigantic those dice look together.
  • msva124 - Thursday, November 2, 2006 - link

    Is the article fully uploaded yet? I got some 404s as I was reading through it.
  • xFlankerx - Thursday, November 2, 2006 - link

    Fine for me now. NIce stuff too, as has come to be expected from AT.
  • Chuske - Monday, December 25, 2017 - link

    I come from the FUTURE !! In very late 2017, beggining of 2018, quad core CPUs are still very much in use .. even QX6700 and people favourite Q6600 (10$ now) held pretty well, for 11 yo cpus ..

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