Since the PCU has a firmware, I wonder if it will be updatable? It would be useful if lessons learn in the power management logic of later steppings and in Westmere can be brought back to all Nehalems through a firmware update for lower power consumption or even better performance with better Turbo mode application. Although a failed or corrupt firmware update on a CPU could be very problematic.

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I thought about this when I read about it the first time too. Flashing your CPU could kill the power management or the whole CPU in one fell swoop!

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"Each QPI link is bi-directional supporting 6.4 GT/s per link. Each link is 2-bytes wide..."

This is actually incorrect. Each link is 20 bits wide, not 16 (2 bytes). This information is on the slide posted directly below the paragraph.

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It's 20-bits but using a standard 8/10 encoding mechanism, so of the 20 bits only 16 are used to transmit data and the other four bits are (I believe) for clock signaling and/or error correction. It's the same thing we see with SATA and HyperTransport.

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... think again.

more luck next time before starting the flamebait about not two bytes wide but 20bits.


effective usable speed is exactly 2bytes, as with 10/8 coding you need 20bits to encode your 16 relevant ones.


you fail at failing.

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Links are 20-bit wide, regardless of encoding or whether 1,2,8,16 or 20 bits are used to tranmist the data.

I wonder who is flamebaiting here, a previous poster just mentioned the correct link width, he wasn't talking about "usable speed".

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I think we're facing a strange issue right now, and it's about the degree of usefulness of Core i7 for the average user. Enterprise clients will surely benefit a lot from all the improvements introduced, but I would have hard time convincing my friends to upgrade from their E8400...

And it's not about badly-threaded applications, the ones an average user has installed simply don't require such immense computing power. Look at your browser, or e-mail client - the tasks they execute are pretty well split over different threads, but they simply don't need 8 logical CPUs to run fast, most of them simply sit idle. It's a completely different matter that many applications who happen to be resource-hungry can't be parallelized to a reasonable degree - think about encryption/decryption, or similar, for example.

It seems to me that the Gustafson's law begins to speak here - if you can't escape your seqential code, make your task bigger. So expect something like UltraMegaHD soon, then try to transcode it in real time... But then again... who needs that? It seems like a cowardly manner to me.

Is it that software is laging behing technology? We need new OSes, completely different ways of interaction with our computers in order to justify so much GFLOPs on the desktop, in my opinion. Or that's at least what I'm dreaming of. The level of man-machine interaction has barely changed since the mouse was invented, and modern OSes are very similar to the very first OSes with a GUI, maybe somewhere in the 80s, or even earlier. But for that time span CPUs have increased their capabilities almost exponentially, can you spot a problem here?

The issue becomes clearer if we talk about 16-threaded octacores... God, I can't think of an application that would require that. (Let's be honest - most people don't transcode video or fold proteins all the time...). I think it would be great if a new Apple or Microsoft would emerge from some small garage, to come and change the old picture for good. The only way to justify technology would be to change the whole user-machine paradigm significantly, going the old way leads to nowhere, I suspect.

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So eventually we may end up with a separate class of systems that are akin to ‘proper’ sports cars with prices to match. Intel seemingly already sees this as a potential which is why they are releasing a separate high end platform for Nehalem. Unless a new killer app or two is found that appeals to the mainstream I can’t see many people wanting to pay a large premium for these systems since as the entry level performance continues to rise less and less people require anything more than what they offer.

One thing mitigating against this is the current relatively low cost of workstation/server Dual Processor components which should continue to be affordable due to the strong demand for them within businesses. It’s foreseeable that it might eventually be more cost affective to build a DP workstation system than a UP high end desktop. This matches Apple’s current product range where they completely miss out on high end UP desktops and jump straight from mid range UP desktop to DP workstation.

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Actually, Windows is the biggest bottleneck there is. Windows doesn't SCALE. It does limited tasks well, but breaks under heavy loads.

Even the M$ guys are realizing this. Midori will likely be the new post-windows OS after Vista SP2 (windows 7).

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It was my understanding that tick was the new architecture and tock was the shrink. I thought Conroe was tick, Penryn tock, then Nehalem tick, and the 32nm shrink tock?

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