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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.
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...
Live today, because you never know what tomorrow brings
The article seems to be down, here's Anandtech's analysis.
I'm pretty sure the parent post was written by a machine. Turing test: failed.
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.
It's really quite amazing how much the hardware has outstripped the ability of software to keep up.
It's not amazing at all. Most desktop applications are single-threaded because you, the operator, are single-threaded. MS Word could enter words on all 100 pages of your book simultaneously, but you aren't able to produce them. An audio player could decode and play 100 songs to you at the same time, but you want to listen to one song at a time...
I can see niche desktop applications where multiple threads are of use. For example, GIMP (or Paint.net or Photoshop) could apply your filter to 100 independent squares of the photo if you have 100 cores. However the gain would be tiny, the extra coding labor would be considerable, and you still need to stitch these squares... all to gain a second or two of a rare filter operation?
The most effective use of multiple cores today is either in servers, or in finite element modeling applications.
It's not amazing at all. Most desktop applications are single-threaded because you, the operator, are single-threaded....
That's a pretty simplistic view. Other than the obvious historical reasons, I believe that most applications are single threaded because the languages and tools for writing non-trivial robust multi-threaded applications is lagging far behind the capability to run them.
> Desktop users think electricity costs.
Bullshit. The difference between a 130W Nehalem and a 65W Core2 is 65W, which is 11 cents per day (at 7c/kW) or $39/year if you run the computer 24/7. Most people turn the computer off when it's not in use, and 8 hours per day is more likely, or 3 cents per day and maybe $10/year. I'd say the cost is entirely negligible, especially when you compare it to your $80/month Comcast bill.