Looking at Nehalem

Let’s start with this diagram:

What we have above is a single Nehalem core, note that you won’t actually be able to buy one of these as it doesn’t include the memory controller, L3 cache and all of what Intel considers to be the un-core. The diagram is drawn correctly; the execution engine isn’t even 1/3 of the core and nearly as much die area is dedicated to the out-of-order scheduling and retirement logic. Now you can understand why Atom is an in-order core.

A single Nehalem core isn’t made up of a majority of cache. Approximately 1/3 of the core is L1/L2 cache, 1/3 is the out of order execution engine and the remaining 1/3 is decode, the branch prediction logic, memory ordering and paging. Obviously this is a bit deceiving since you’re only looking at the core here, the un-core includes a massive 8MB L3 cache which changes the balance of things considerably:

Here we have a full quad-core Nehalem. What Intel calls the un-core is the L3 cache, the I/O, the memory controller logic and the Quick Path Interconnects (QPI). Desktop Nehalem processors will only have one QPI link (QPI 0) while server/workstation chips will have two (QPI 0 and QPI 1).

The Nehalem architecture is designed to be scalable and modular, you will see dual-core, quad-core and eight-core versions in 2009:

Some versions of Nehalem will also include a graphics core, it will be located in the "un-core" of Nehalem as you'll soon see. The graphics won’t be Larrabee based, it will simply be a derivative of the current G45 architecture.

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  • qurious69ss - Friday, August 22, 2008 - link

    You sound like one of those sad fanboys from amdzone. Tell dimentia to get a life.
  • X1REME - Friday, August 22, 2008 - link

    wow, this whole cpu is a copy of a amd cpu and you expect amd fan boys to not get amd with you, secondly this fantasy is baseless until you can compare it to an offering from the AMD team (Shanghai & Deneb). AMD is still KING with there OPTERON and most likely will be in the future with there new cpu coming soon for the server and also for the desktop.
  • DigitalFreak - Friday, August 22, 2008 - link

    Learn to spell, you goober.
  • X1REME - Friday, August 22, 2008 - link

    OK DORK, am sure you have never made a mistake (there=their) Duh. I bet your some kid all hyped up for the i7 who wishes Xmas comes early lol. Anyway it’s not a desktop chip, it’s a sever chip DUH. It’s meant to compete with the AMD Opteron chip (the best). Although Opteron will lose its crown, it won’t be to i7 but to Shanghai (AMD new latest and greatest). And like I said b4, Deneb will clear anything up out of place.

    The reason amd does not grab a microphone and star shouting at the top of their voice is because amd doesn't have the resources and money in comparison with Intel. If it reveals too much about its future strategy and Intel likes that strategy (like the Opteron, HT, On-board mem etc) there is a big theoretical chance that Intel could take this idea and deliver a product well before AMD. So it’s not over until amd says its.
  • snakeoil - Thursday, August 21, 2008 - link

    nehalem fails,it was supposed to be superior to core 2, intel was against the wall this time, why?, because, the old front bus architecture was lagging more more in the server arena and becoming a bottleneck ,compared to hypertransport, so intel is forced to abandon the front side bus, but the strong point of core 2 is that because you don't have and integrated memory controller you can stuff the processor with a huge L2 cache.
    so, nehalem sucks in gaming,there is no way that the enthusiast is going to pay more for a processor that produce less fps that they actually have.
    and the hyperthreading is a risky move, hypertrheading is known por being power hungry, and although produce gains in some applications,some servers applications actually runs slower, so in many cases the old hyperthreading had to be disabled.
    nehalem is crippled for the enthusiast,and the regular user.

    nuff said.
  • AssBall - Saturday, August 23, 2008 - link

    You musta missed where Anand says several times its not intended for better gaming? It will be significantly faster than Penryn for multithreaded applications. I guess I don't see how this makes it "fail". Maybe in your fantasy world where 90% of the CPU market are "enthusiasts".

  • snakeoil - Saturday, August 23, 2008 - link

    enthusiasts drive the market you fruityass
  • UnlimitedInternets36 - Saturday, August 23, 2008 - link

    LOL this year Satan err Santa is going to take away your PC because you don't deserve to have one anymore You Jaded nerd.
  • Gasaraki88 - Friday, August 22, 2008 - link

    Thanks! I never knew there was a expert on CPU design in the house. I've learn so much from your well researched, tested and thought out comment...
  • pool1892 - Friday, August 22, 2008 - link

    first of all the enthusiast market is a very tiny niche, it would not kill intel if you were right.
    but you are not. the L2 of penryn (and banias) is much more like the nehalem L3 than the nehalem L2. and if you have a single threaded game it now has 8mb at similar latencies, but with a second buffer, the 256k L2, and a MUCH smaller cache miss penalty.
    concerning hyperthreading: please read the article first. nehalem switches off what it does not need, powerwise. and about fiftytwo other very vaild arguments.

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