Overclocking

When Intel's first dual core CPUs hit the market, there was a significant gap in clock speed between them and the fastest single core CPUs. The fastest dual core Pentium Extreme Edition was introduced at 3.2GHz, while you could get a 3.73GHz single core CPU for similar money. The single core Pentium 4 Extreme Edition had a 16.5% clock speed advantage, that you had to give up in order to get a second core at the high end.

Of course back then, clock speed mattered, and it was frequency that got you reasonable performance out of Intel's NetBurst architecture. You gave up much less if you looked at the AMD side of things; their fastest single core CPUs at the time ran at 2.6GHz while the fastest dual core Athlon 64 X2s ran at 2.4GHz.

With Intel's Core microarchitecture, the situation with Kentsfield vs. Conroe is much more like the Athlon 64 vs. Athlon 64 X2. At $999 you've got a dual core 2.93GHz offering or a 2.66GHz quad core offering, and at that price point the decision isn't too hard to make, especially when you take into account that you can overclock Kentsfield pretty well.

Like all other Core 2 Extreme processors, the QX6700 has a mostly unlocked clock multiplier, allowing you to easily overclock to higher frequencies. So while you can't take a Core 2 Extreme X6800 and give it more cores, you can always take a QX6700 and run it at X6800 speeds to have your cake and eat it too.

We managed to get our QX6700 sample up to 3.2GHz (12 x 266MHz) at the CPU's stock voltage of 1.35V, which isn't bad at all considering we didn't employ any exotic cooling. Bumping the core voltage up to 1.3875V we were able to gain an extra 266MHz and run at 3.46GHz.

You lose some overclocking headroom given the added heat output of the extra die on the chip, not to mention that both die have to be capable of running at the overclocked speed, but overall Kentsfield doesn't look too bad as an overclocker's chip. It's not the bang for your buck that the E6300 offers, but at $999 that's not what we're expecting to begin with.

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  • Sharky974 - Friday, November 3, 2006 - link

    Dudes, I remember reading, with detailed benchmarks from a site that specialized in HDD's, that raid array's for speed are COMPLETELY AND UNEQUIVICABLY USELESS.

    It bugs me too, because then as now, people just refuse to accept that fact, even with benchmarks proving it over and over staring them right in the face. RAID DOES NOT SPEED UP YOUR SYSTEM. PERIOD.

    If you want to use it for auto backup otoh, fine..
  • cjb110 - Thursday, November 2, 2006 - link

    One question I would like answered, would a quad core help with the gaming and background task usage? (i.e. IM, P2P etc etc) Is Windows intellegent enough to use those cores properly?

    Reason I ask is I'm planning to go from a 2 pc setup (1 gaming, 1 background tasks) to a single setup, and wondering if quad would be an even better solution for me?
  • Sunrise089 - Thursday, November 2, 2006 - link

    Probably not. While this sounds like a good idea, the main benefit in going dual-core is offloading 100% of those background tasts to the second core, so the game gets one core all to itself. Moving from two to four does almost nothing because there isn't anything else to unload. Now, in the future there will be more titles that will use 2 cores, so 4 core chips have their uses, but by then most readers of this site will have upgraded again anyways.
  • JarredWalton - Thursday, November 2, 2006 - link

    Depends on the background tasks. If you're running something in the background like media encoding, which can already easily use two cores, I would expect quad core to do better. If you're running BitTorrent plus media encoding plus a TV recording application, then I would expect even more benefit if you try to game. Of course, if you're doing all that, you better have a nice HDD configuration as well. RAID 0 with NCQ enabled should suffice.
  • Sunrise089 - Thursday, November 2, 2006 - link

    Ok, sure, but when most people ask this question they are talking about a game plus IM and anti-virus and maybe a Firefox window. Not all that many people play fullscreen games while encoding files and bittorrenting.
  • JarredWalton - Thursday, November 2, 2006 - link

    Right, in which case there's little difference, at least right now. When games start coming out that can use multiple cores (not just 2 or even 4), then it could become a lot more important. For now, dual cores is plenty for 99% of people.
  • shabby - Thursday, November 2, 2006 - link

    I love it how steve jobs is pimping the intel chip now, before his ppc chips were oh so much faster then intel chips. What a two faced whore...
  • Donegrim - Thursday, November 2, 2006 - link

    But before his ppc chips WERE more powerful than Intel ones. Before the core architecture came into being. Now the core is faster than the ppc, so he is using them. Makes sense really, I'm sure I'd do the same.
  • Griswold - Thursday, November 2, 2006 - link

    Nah, he was cursing the whole x86 architecture. By your logic, he could have went with AMD while Intel was touting their netburst furnaces.
  • peternelson - Thursday, November 2, 2006 - link

    "4x4 is an entirely new platform using Socket-1207 (not AM2) CPUs. As much as AMD wants 4x4 to succeed, what we're really waiting for is Barcelona. "

    HAS AMD ANNOUNCED CLEARLY that 4x4 will be only 1207 and NOT AVAILABLE for AM2?

    In earlier announcements it looked like 4x4 would be AM2 (hence speculation about how it could dual socket without extra hypertransport links). PLEASE STATE IF AMD HAVE MADE AN UNAMBIGUOUS STATEMENT OR CLARIFICATION TO THIS EFFECT. Note 4x4 and the acceleration coprocessor tech are two different technologies and might be confused if they are in the same conference/press release or anandtech article.

    In any case AMD promised 4x4 during 2006, so we will know the answers real soon ;-)

    I think 4x4 will not be nice just for two dualcores, but for have TWO QUADCORES. Now depending on if those quadcores can be AM2 or 1207 or available for either, that will alter the price/performance of AMD's offering.

    However I am looking forward to an 8 core system from AMD.

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