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Inside Intel's Core i7 Processor, Nehalem

MojoKid writes "Intel's next-generation CPU microarchitecture, which was recently given the official processor family name of 'Core i7,' was one of the big topics of discussion at IDF. Intel claims that Nehalem represents its biggest platform architecture change to date. This might be true, but it is not a from-the-ground-up, completely new architecture either. Intel representatives disclosed that Nehalem 'shares a significant portion of the P6 gene pool,' does not include many new instructions, and has approximately the same length pipeline as Penryn. Nehalem is built upon Penryn, but with significant architectural changes (full webcast) to improve performance and power efficiency. Nehalem also brings Hyper-Threading back to Intel processors, and while Hyper-Threading has been criticized in the past as being energy inefficient, Intel claims their current iteration of Hyper-Threading on Nehalem is much better in that regard." Update: 8/23 00:35 by SS: Reader Spatial points out Anandtech's analysis of Nehalem.

9 of 146 comments (clear)

  1. only the super high desk tops have Quick Path and by Joe+The+Dragon · · Score: 4, Interesting

    only the super high desk tops have Quick Path and Triple channel DDR3 and the bigger joke is the that there will be 2 differnt 1 cpu desktop Socket.

    also the mobile will not have Quick Path.

    all AMD cpus use hyper transport and all desktops will use the same socket and the upcoming AM3 cpus will work in the older am2+ boards. Also on amd you can use more then 1 chipset will intel it looks like you will be locked in to a intel chipset.

  2. Power effiiency is the new "it" by Kjella · · Score: 5, Interesting

    Nehalem is really the realization of what many slashdotters have claimed before - the typical user doesn't need that much more performance. Both datacenters and laptop users ask for the same thing - power efficiency - and Intel delivers. The Atom is another part of the strategy, even though it's current coupled with a very inefficient chipset.

    The thing is, today we have the knowledge and complexity to fire up kilowatt systems and more - but they're costly running. Certainly there's the extreme hardcore gamers who won't mind running the hottest, most powerhungry quad crossfire system, but they're few and far between. Laptop users think battery life. Desktop users think electricity costs. The result is Nehalem, which promises to deliver a lot more performance per watt.

    If the practise is as good as the theory, AMD is unfortunately in deep shit. They've always been good at delivering ok processors at an ok price, but power efficiency has really only been their strength compared to the Netburst (PIV) processors, not P3 or the Cores. If it amounts to "yeah your processors are cheaper but they cost more to operate" things will fall apart, which is sad since ATI is really doing fine. The 48xx series are kick-ass cards, I just hope they can keep up the competition against Intel...

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    Live today, because you never know what tomorrow brings
    1. Re:Power effiiency is the new "it" by Kneo24 · · Score: 5, Interesting

      You are behind the times. ATI cards, as far as price vs performance, are spanking NVidia's cards with moon rocks. I think a big helping hand in that is that for whatever reason, AMD said to them, "make better drivers, or else!".

      Also, AMD has gone the route of trying to be more open source friendly with their cards, more so than NVidia.

      Currently, you just can't go wrong with owning a current generation Radeon card right now.

    2. Re:Power effiiency is the new "it" by distantbody · · Score: 3, Interesting

      Nehalem is really the realization of what many slashdotters have claimed before... ...power efficiency - and Intel delivers.

      Putting the cringe-worthy PR tone aside (are you connected to intel in any way?), the lowest-clocked 'mainstream desktop' Bloomfield CPU (running at 2.66 GHz, 45nm, quad-core) has a TDP of 130W! Now, efficient or not, that is one hot-and-sweaty processor, making me wonder that if Nehalem truly does have '1.1x~1.25x / 1.2x~2x the single / multi-threaded performance of the latest Penryn ('Yorkfield', 2.66GHz, 45 nm, quad-core, 95W TDP) at the same power level', why wouldn't they let the efficiency gains carry the performance increase of Nehalem for the same TDP?

      Look I may or may not be missing something, but I have been reading plenty of (uncomfortably positive, perhaps bankrolled) material on nehalem, yet I can't shake the perception that, with a huge TDP increase, the return of hyperthreading and the cannibalization of L2 cache for L3 cache, Nehalem seems far more Pentium 4 than Penryn.

  3. Re:Here we go again by Traiano · · Score: 5, Interesting

    Don't assume that since Hyper-Threading failed with Netburst that it is forever doomed to fail again. The primary problem with that architecture was that stages along the pipeline didn't support multiple threads. So, any thread context switches forced a flush of Netburst's very, very long pipeline. Intel's next generation of pipelines track multiple threads at all stages and make the prospect of HT much more attractive.

  4. Re:only the super high desk tops have Quick Path a by beakerMeep · · Score: 4, Interesting

    Take a deep breath. It's OK if AMD and intel both have good chips. The question really comes down to the brand of salsa anyways.

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    meep
  5. Re:only the super high desk tops have Quick Path a by hairyfeet · · Score: 4, Interesting

    Actually I don't know if they are cutting their own throat or not,but I have noticed I'm building a lot more AMD machines lately. And for the first time since the old K2(IIRC,they were the 400MHz ones) I am actually looking at building an AMD board for myself. The price on AMD dual cores has just gotten so cheap I can cut a good 35% off the cost by going AMD. But for most folks the X2 series has enough power that it is frankly overkill. But as always this is my 02c,YMMV

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  6. Intel Will Regret This by Louis+Savain · · Score: 3, Interesting

    More than any other organization, Intel knows that multithreading is bad. Lots of smart people such as professor Edward Lee (the head of U.C. Berkeley's Parallel Computing Lab) have warned Intel of the disaster down the road. It is time for Intel and everybody else to make a clean break with the old stuff. There is an infinitely better way to design and program parallel computers that does not involve the use of threads at all. Instead of the Penryn, Intel should have picked something similar to the Itanium, which has a superscalar architecture. A sequential (scalar) core has no business doing anything in a parallel multicore processor. Intel will regret this. Sooner or later, a competitor will read the writings on the wall and do things right. Intel and the others will be left holding an empty bag. To find out the right way to design a multicore processor, read Transforming the TILE64 into a Kick-Ass Parallel Machine.

  7. Re:Here we go again by Waffle+Iron · · Score: 3, Interesting

    Hyperthreading can make a lot of sense in some circumstances. Sun pushed hyperthreading to its limits to achieve very impressive energy efficiency for certain niche workloads with its Niagra CPUs and derivatives. (IIRC, up to 128 threads per chip.)