Dual Core Mobility

A while ago I asked Pat Gelsinger what was in store for the future of Pentium M with regards to threading, and he responded with multi-core. Thus it's no surprise to finally see Intel giving more details about Yonah (or Jonah depending on what part of the world you're from), the 65nm dual core successor to Dothan.

Yonah's dual core setup will be much more power optimized than what Smithfield will bring to the desktop, and in an effect, much more efficient. There's little information available about Yonah, other than it will most likely have a power and thermal balancing dual core setup, with the individual cores powering down when they're not needed. The idea here is to switch between cores not based on performance needs, but based on thermal and power needs. If one core happens to be running too hot, it can be powered down and the active workload shifted to a different thread running on the remaining core, thus reducing the problem of thermal density by effectively spreading the thermal load across two cores.

While Dothan was more of a small set of fixes and updates to Banias, Yonah is going to be a significant set of improvements to what we've seen in the past. Yonah has already taped out and Intel is slated to release the chip in 2006. Yonah will begin sampling by the end of 2005 and Intel expects it to ramp up to 50% of the performance notebook segment by the end of 2006.

Yonah's platform is codenamed Napa, which brings support for DDR-2 667 as well as the 667MHz FSB to help keep the dual core Yonah fed with data. Given that Dothan will ramp to 2.26GHz by the end of 2005, we can expect Yonah's clock speeds to be around there upon its launch.

Dual Core Servers

Most recently Intel announced that their only multi core enterprise product shipping in 2005 would be Montecito, the dual core version of Itanium 2. This is where the rumor of Intel not shipping any dual core chips until 2006 came from, as it seems that the first dual core Xeons won't ship until Q1 2006. Now as long as Intel's desktop chips don't face any further delays, there will still be dual core desktop CPUs based on Smithfield available by the end of 2005. Given Intel's track record lately, it would not be surprising to see these chips slip into 2006 as well though.

The first dual core Xeons appear to be nothing more than Xeon versions of Smithfield, but Intel does list that more power efficient versions of the first dual core Xeons will appear in the second half of 2006 - potentially including some of the power management features that will be included in Yonah.
An interesting inclusion on Intel's dual core Enterprise roadmaps is the mention of a Dual Independent Bus. The term Dual Independent Bus hasn't been used since the days of the Pentium III to indicate the separation of the internal L2 cache bus from the external Front Side Bus. However, we wonder if the dual core Xeon's Dual Independent Bus may in fact be individual 64-bit datapaths to each socket on a dual socket server. This way a pair of dual core Xeons would have just as much FSB bandwidth per pair of cores as the present day dual processor Xeons, which will end up improving performance tremendously.

The platforms that will enable dual core Xeon support will be Blackford and Greencreek for 2S (two Socket) systems, and the next generation Twincastle for 4S systems.

Index The Problem with Intel's Approach and AMD's Strategy
Comments Locked

59 Comments

View All Comments

  • ChronoReverse - Saturday, October 23, 2004 - link

    @48

    And Windows reports 10 threads for the UT2K4 demo. I still know that it's not really designed to take full (by full I mean special) advantage of multithreading.
  • Chuckles - Saturday, October 23, 2004 - link

    #37
    According to 'top' on Mac and Task Manager on Win XP:
    Escape Velocity: Nova - 7 threads
    Robin Hood: Legends of Sherwood (Demo) - 5 threads
    Airburst Extreme (Demo) - 8 threads
    Homeworld 2 (Mac Demo @ 1st mission, 2nd save) - 8 threads
    Homeworld 2 (PC Demo @ 1st mission, 2nd save) - 8 threads

    All seem to be reporting multiple threads.
  • Sunbird - Saturday, October 23, 2004 - link

    I have a question that just popped into my mind,

    Will the dual core processors from AMD and Intel technically be two 64bit cores?

    If it is, man, you get dual core and 64bit all in one, seems it will be pretty cool (but not those dual core prescotts :P ) when you have both of those steaming away with software written for them.
  • AdamK47 3DS - Saturday, October 23, 2004 - link

    I envision more marketing behind the dual core CPUs than performance numbers to sell these. Most people (as is proven by the responses here) will think their getting double the performance simply because they are "dual cores". Dual cores require multithreading capabilities to truly take advantage of them in a single app. If you're a gamer there aren't very many games out there that are multithreaded. Even most games coming out in the next couple years won't be multithreaded. Multithreading can be cumbersome to programmers.
  • AdamK47 3DS - Saturday, October 23, 2004 - link

  • Reflex - Saturday, October 23, 2004 - link

    Just to make one thing clear: I like dual core, I think it is a good move, I can't wait to get mine...

    However, you will not see 100% improvement on a dual core system, not even close, even with multi-threaded apps. At best you will see 80% in *some* situations, in most circumstances its more like 40-50%. The thing to remember here is that those dual cores are sharing the rest of the system with each other, so a straight 100% improvement is impossible due to the fight for system memory and resources. This is exacerbated on shared bus designs like the P4, but even in the case of the Athlon64 there are some shared resources..
  • xsilver - Saturday, October 23, 2004 - link

    #42 I think you answered your own question
    "Within a year or two, you will be buying (essentially) 6 to 8 GHz CPUs, instead of 3 to 4 GHz CPUs."
    Essentially this 6ghz cpu is no better than the 3ghz cpu on one program -- its all fine and dandy to be able to run 2 programs just as fast with no performance hit but when advertisers say it runs X fast, that X would not have changed; only you can run X and Y at the same time.... Its not double performance, its more like HT overdrived.... you mention MMX, sse etc. they are good features cause they add no cost/ heat into the equation whereas dual cores may double the processor on both counts here...
    The INTEL spin doctors though will spin it so it sounds good until software can use the multithread properly...
  • theprofessor - Saturday, October 23, 2004 - link

    I don't know why everyone seems so against dual core CPUs. I have been waiting years for this (as I was for 64-bit CPUs). Most people will see an increase in performance using a dual core CPU. I don't care if the program is single threaded or not. Most people run more than one program at a time. All modern Operating Systems (including XP) will allocate time on both cores for different processes. So, while you’re playing your single threaded game on one core, you can run your encoding software, anti-virus software, im software, e-mail software, download software, whatever software on the other core, with no hit to performance. If you don’t play games, include whatever single threaded software you like. There will be a decent boost to performance no matter what you are doing.

    Dual core is the best upgrade a processor can get. Why? Because with MMX, SSE, SSE2, 3D Now!, and, especially, 64-bit, there needs to be re-programming and/or re-compiling involved to notice any difference at all. With dual core you will notice a difference in almost all modern computing paradigms the day the chip is released. And as the technology becomes more mature and prevalent, you will notice even more performance as developers re-program/re-compile there software.

    Computer enthusiasts should be looking at this as a doubling of computing performance. Within a year or two, you will be buying (essentially) 6 to 8 GHz CPUs, instead of 3 to 4 GHz CPUs. As far as pure performance increase, I think this could be the greatest technology ever introduced to a processor line. No other technology (listed above – MMX, etc.) has been able to give almost 100% performance increase (theoretically) across the board in all applications.

    If nothing else, think of it this way. With the ramp in CPU frequency drastically slowing over the last two years, going forward it will now be at least double what it would have been. (i.e. If AMD and Intel can currently only handle 200 – 400 MHz frequency increase in a year, with dual core that becomes 400 – 800 MHz.)

    It’s a win almost every way you look at it. So please, try not to be so critical of this great technology.

    Thank you
  • Reflex - Saturday, October 23, 2004 - link

    #37: If that were true then every ported PC game would take years to rewrite and bring to the Mac since they are not designed multi-threaded in the first place(and most Mac games are PC ports).

    Don't confuse the fact that you can multi-task while playing a game with the idea that the game itself is multi-threaded. They are not the one and the same, and you can multi-task while playing a game on Windows as well...
  • thermalpaste - Saturday, October 23, 2004 - link

    Intel could have launched the dual core using the P6 architecture as in the pentium-M processor. If they still love high clock speeds, maybe they can deepen the pipelines a bit for the p6. With prescotts touching 65 degrees plus, the dual cored pentium-4s may need car radiators in order to overclock;). Its obvious that the dual cores only come into play for multi-threaded apps, so perhaps intel can shift back to p6 when majority of apps support multi-threading.

Log in

Don't have an account? Sign up now