Experiment: Does Intel’s Turbo Boost Trump Overclocking?

Setting Up The Comparison

Processors

As mentioned, we used retail Core i5-750 and Core i7-860 processors in this experiment—probably the two most likely candidates for the enthusiast treatment. The i5 is a sub-$200 component shown to reliably hit 4 GHz or more, while the i7-860 is a sub-$300 alternative that adds Hyper-Threading support, a 2.8 GHz base clock rate, and one extra bin of Turbo Boost with a single-thread active.

Our Core i7-860...Our Core i7-860......and our Core i5-750...and our Core i5-750

Why no Core i7-920? That’s also a completely viable option, especially if you tend toward high-end gaming and need the extra PCI Express 2.0 connectivity afforded by Intel’s X58 chipset. But for roughly the same price as our Core i7-860, the -920 adds a third memory channel, loses 133 MHz of base clock frequency, and isn’t as aggressive with its Turbo Boost binning. Additionally, buying the LGA 1366-based chip means investing in a pricier X58-based motherboard, too. Lynnfield and P55 are probably more representative of what value-oriented enthusiasts are going to want from a new build.

Motherboard

Our choice of motherboard might leave some folks scratching their heads, but there’s sound reasoning behind going with Intel’s DP55KG.

First of all, the technical reasons: our go-to for this one was Asus’ Maximus III Formula. But after updating the board to the latest BIOS posted on the company’s site, it no longer ran stably with our retail CPU and Corsair Dominator memory kit. Hoping this was just a fluke, we swapped over to Gigabyte’s P55A-UD6, which ran wonderfully with Turbo Boost turned on, but got all choppy when Turbo Boost was manually disabled. Benchmarks would run fine, but actually launching apps and navigating through Windows felt as if our powerful machine was a decade-old Pentium II.

So, hoping for an easy remedy, we swapped over to Intel’s DP55KG, which performed well in Thomas’ most recent P55 motherboard roundup. If any board was going to work properly, we surmised, it’d be Intel’s own enthusiast-oriented offering. And sure enough, the Kingsburg board did the trick, and we were back on track.

The rest of our choices were designed to minimize bottlenecks. ATI’s Radeon HD 5850 is what we’d consider to be the best enthusiast buy right now, and a second-gen Intel 160GB SSD alleviates pressure on storage. Two 2GB modules of Corsair’s DDR3-1600 Dominator GT DDR3-2200 8-8-8 memory allowed us to run at DDR3-1600 frequencies without any stability issues.

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    Top Comments
  • Great article. On another note, the useless Mass Effect 2 ad blaring it's stupid music in my ears at every new page is really starting to piss me off.
    23
  • i play GTAIV online alot - your e8400 gets left in the dust there sorry PhantomTrooper, and theres no adverse effects having spare cores for future use with newer games etc
    21
  • I would like to see how a minor OC with Turbo enabled would stack up.
    18
  • Other Comments
  • No one needs a Core i7 for gaming. I'm still using a e8400 with a gtx275 and I run everything fine at 1080p, even Crysis.
    2
  • i play GTAIV online alot - your e8400 gets left in the dust there sorry PhantomTrooper, and theres no adverse effects having spare cores for future use with newer games etc
    21
  • I second that, PhantomTrooper. I'm on a slightly lower end spec PC than you're using (Athlon 7750 with Radeon HD4830) and with it hooked up to my 1366x768 TV through VGA, everything I play maxes without lag. Mind you, I don't play any titles that are extremely demanding, but I'm playing 2008 and 2009 titles maxed out, on a $60 CPU and an $80 video card.
    1
  • Great article. On another note, the useless Mass Effect 2 ad blaring it's stupid music in my ears at every new page is really starting to piss me off.
    23
  • Yeah, you guys are going to get a kick out of the upcoming Clarksdale story. It's amazing how badly a Core 2 Duo E8500 gets killed by a Phenom II X4 or Core 2 Quad in some of these more optimized titles.

    Curnel--sorry about the ad. I also find it pretty annoying to play automatically every time I open a page for proofing. I'll ask about it.
    16
  • Nice article.I agree about the annoying video ads that Curnel_D mentioned earlier.
    0
  • Curnel_DGreat article. On another note, the useless Mass Effect 2 ad blaring it's stupid music in my ears at every new page is really starting to piss me off.


    Thanks Chris for your courtesy.
    0
  • Curnel_DGreat article. On another note, the useless Mass Effect 2 ad blaring it's stupid music in my ears at every new page is really starting to piss me off.

    I know it's not a viable solution for all, but I never have my sound on... so I didn't even notice the advert (other than seeing it.)
    -4
  • I have been building computers for myself family and friends for years and I remember some of the different ways utilized to speed up your computer (including the turbo button on your computer). This method seems like a viable way to speed up computers of those of us that don't really want to overclock.

    On a side note: Woot!!! I just saw the Mass Effect 2 ad has been removed. It did have the option to mute it but it was removed fast enough I didn't have a chance to check to ensure it saved to all pages. Thanks Tom's.
    0
  • Nope I was wrong I guess it was random and just didn't come up for a while and the mute does not save :(.
    0
  • AbBlock :)
    6
  • Indeed, Adblock all the way. It's a necessity these days.
    10
  • It was quite obviously already the only useful purpose for Turbo Boost is if the chip ran @stock. With it enabled it hinders scaling potential greatly. What I found most useful in this article is it provided more data on which programs benefited from the 'new & improved' Hyper-Threading.
    0
  • Interesting article. What I don't understand is every time a pc website, magazine article, or review refers to the difference in system cost for value consumers vs. high end or performance consumers.

    There is a considerable price overlap for the low to high range for a 1156 i5/i7 system and the low to high range for a 1366 i7 system.

    The system assembled for the testing of the value oriented consumer system in this article with out OS is $1700+ at Newegg! Of course, as Chris Angelini points out in the article, the non chipset specific components (GPU, PSU, SSD and heat sync) were chosen to remove potential bottlenecks to facilitate a reliable review.

    If you add up the current Newegg cost Intel Core i7-860, Intel DP55KG, and CORSAIR DOMINATOR 4GB DDR31600 (PC3 12800) alone it is $653.97 while the Intel Core i7-920, "Tom’s Hardware 2009 Recommended Buy" ASRock X58 Extreme LGA 1366, and CORSAIR DOMINATOR 6GB DDR3 1600 (PC3 12800) total $683.97. The performance gains, better feature set (triple channel memory/3 x PCI Express 2.0 x16 slots) and future upgrade options (SLI and Crossfire support) of the X58/1336 based system are well worth the extra $30! These prices are not even shopping around for deals on the components, since Microcenter has had the i7 920 for $199.00 since launch and you can save $88.00 and add the saving back into a better GPU or mobo or save the extra money for a real value.

    Don't believe the hype from Intel about the "value" and "enthusiast" product lines. The only difference is Intel's greater profit margin on the stripped down Lynnfield and P55 chips.
    6
  • I would like to see how a minor OC with Turbo enabled would stack up.
    18
  • I've got the i7-975 quad core on a DFI LP UT X58-T3eH8 motherboard.
    I'm finding the Turbo feature great. If the CPU workload decreases, the clock rate decreases allowing the system to cool down. There is no messing with RAM voltages. Only turning on the feature in the BIOS. Even I could do that.

    Also, this is a designed feature. You're not trying to run the CPU faster than it was designed to run as is often the case with overclockers and there is no trial and error with possibly burning out your CPU. I love the Turbo feature.
    0
  • dfuscoI would like to see how a minor OC with Turbo enabled would stack up.

    I agree, I am currently gunning my i7 920 at 3.2 ghz on stock cooling, and with turbo boost enabled, the clock increases to 3.3ghz when the multiplier increases from 20 to 21. Without turbo boost, I am not able to reach a multiplier of 21 because of the limitations on the processor, and correct me if I'm wrong, but disabling turbo boost also disables speed step, so my processor would always run with a multiplier of 20 instead of scaling back to a multiplier of 12 when it is idle.
    2
  • dfuscoI would like to see how a minor OC with Turbo enabled would stack up.

    Same here. It seemed to work well for the $1300 SBM.
    1
  • Could we see an apples-vs.-apples comparison of load power usage as well please? Such as Prime95 running for 10 minutes on all (virtual) cores, for example.

    I've read a fair few reviews on the socket 1156 processors and they have all pointed to significant overclocking/overvolting absolutely wrecking power statistics with a draw some three _times_ the base model. Sometimes more.
    0
  • this is actually nice , i dont have to overclock my i5 for any game out there ... with powerful single gpu's here , looks like i would be happy without 1366 , sli or CF ... with an easy 3.6 oc when i need it , i think this would last me at least 3 years ... same for any body who has phenom 2 x4 , q9xxx (even q6600) , they're all powerful and can oc well .. the only sad thing's that have happened to gaming this year is radeon's higher than launch prices and delayed fermi .
    0