Is the article fully uploaded yet? I got some 404s as I was reading through it.

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Fine for me now. NIce stuff too, as has come to be expected from AT.

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Damn.. I can't get over how gigantic those dice look together.

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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.


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

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

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

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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.

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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).

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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 :)

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The article seems to state that Kentsfield is more efficient that Conroe. This conclusion comes from power measurements of complete systems. This is a little misleading, since a large chunk of that power is consumed by the rest of the system. Since the CPU only makes up a part of the power consumption, but accounts for a very large performance increase, the efficiency is bound to increase when looking at system power consumption.

The Kentsfield CPU itself shouldn't be any more efficient than Conroe. That said, there isn't anything wrong in looking at system power consumption and drawing the conclusion that the computer is more efficient with the quad core. I just don't think that the article was very clear on this, though.

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Yeah i agree, the more the rest of the system uses, the more "flawed" the numbers will be, lets say, for arguments sake, that a CPU uses 50 watts, and a twice as fast one uses 200 watts. Tut the rest of the system uses 300 watts, then the total system will use 350 watts in the fist case, and the twice as fast one will use 500 watts, so if you take the whole system numbers, the more power-hungry core will seem like it gives more permformanve per watt, but if you only look at the CPUs them self, the picture is diffrent, the less powerhungry CPU has twice the performance per watt.

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You are right that we could be more clear. You can think in terms of efficiency that we're looking at two dual core systems vs. one quad core if you'd like. If we could isolate just the CPU power draw, we could get real CPU efficiency, but doing so is very difficult.

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Some sites have indeed isolated the CPU power draw by modifying mobos so that current draw as well as voltage on certain pins can be measured. It is, as you say, very difficult however and each platform you wish to test needs its own modded mobo.

One simpler way to at least get a rough idea of actual power comsumption (which could be easily calibrated to provide more accurate figures), and a quite accurate measure of relative power consumption would be to measure the heat given off rather than the electricity going in.

The most obvious way to do that would seem to be with a modified water-cooling setup where instead of the heat being dissipated by an external radiator into air, it is instead transferred into a *large* insulated tank of water with an accurate digital thermometer monitoring the water temperature. This tank of water is not circulated through the water-cooling system, it is there merely for the heat to be dumped into. You then measure the rate at which the temperature rises which provides a good guide to power consumption. You might start at 20C and could probably run the tests up until the water reaches about 40C without any problems, probably 45C would still result in the CPU being kept within safe temperatures.

With a 10-litre tank, you would have 10Kg of water, and each Kg requires about 4.2KJ of energy to heat up by 1C, so it would take about 42KJ to heat up that tank of water by 1C. 42KJ is equivalent to 42KW for 1 second, or more realistically, 42 watts for 1000 seconds (about sixteen and a half minutes). You can probably see where I'm going here: a processor using about forty watts of power would heat up the tank of water by about 4C per hour. Eighty watts would be 8C per hour, and so on. Although not all the energy used by the processor will be dumped in the water due to heat being lost elsewhere, the vast majority of it will be and it will be consistent between different processor models.

If you want an exact figure for power consumption, or rather heat dissipation, then the system could be calibrated by connecting it to a CPU shaped heater element fed with a measured amount of power. Take measurements of the rate of temperature rise at twenty watt intervals up to say two hundred watts (I suspect the line will be fairly linear above about 40W) and you can now say with a good degree of accuracy how much power a given CPU is actually using.

As I say, that's one way you could do it and one which in theory should work very well.

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