Overclocking and 22nm

In the old days, whenever Intel transitioned to a new manufacturing process it was accompanied by increased overclocking headroom thanks to the reduction in power consumption and increase in switching speed afforded by the new transistors. To be honest, it's surprising the ride has even lasted this long.

Intel's 22nm process (P1270) is the most ambitious yet. The non-planar "3D" transistors promise to bring a tremendous increase in power efficiency by increasing the surface area of the transistor's inversion layer. It's the vehicle that will bring Intel into new form factors in mobile, but we're around a year away from Haswell's introduction. Rather than 22nm being a delivery platform for Ivy Bridge, it feels like Ivy Bridge is being used to deliver 22nm.

The process is still young and likely biased a bit towards the lower leakage characteristics of lower voltage/lower wattage CPUs, such as those that would be used in Ultrabooks. These two factors combined with some architectural decisions focused on increasing power efficiency result in what many of you may have heard by now: Ivy Bridge won't typically overclock as high as Sandy Bridge on air.

The frequency delta isn't huge. You'll still be able to hit 4.4—4.6GHz without resorting to exotic cooling, but success in the 4.8—5.0GHz range will be limited to water alone for most. Ivy Bridge is also far more sensitive to voltage than Sandy Bridge. Heat dissipation can increase significantly as a function of voltage, so you'll want to stay below 1.3V in your overclocking attempts.

Dr. Ian Cutress, our own Senior Motherboard Editor, put Ivy Bridge through a pretty exhaustive investigation if you want more details on exactly how the chip behaves when overclocking and how best to overclock it.

For the past few years I've been focused on power efficient overclocking. I'm looking for the best gains I can get without significant increases in core voltage. With my 3770K I was able to reliably hit 4.5GHz with only a 140mV increase in core voltage:

The end result is a 15—28% overclock, accompanied by a 32% increase in power consumption. The relationship between overclock speed and power consumption actually hasn't changed since Ivy Bridge, at least based on this datapoint.

Ivy Bridge Overclocking
Intel Core i7 3770K Stock 4.6GHz Overclock % Increase
Load Power Consumption 146.4W 204W 39.3%
x264—2nd Pass 41.8 fps 49.5 fps 18.4%

As always, your mileage may vary depending on the particular characteristics of your chip. Ivy Bridge can be overclocked, but at least initially it's not going to be as good of an overclocker as Sandy Bridge. Over time I expect this to improve somewhat as Intel's 22nm process matures, but by how much remains a question to me. It's unclear just how much of these limits are by design vs. a simple matter of process maturity.

Die Size and Transistor Count The 7 Series Chipset & USB 3.0
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  • sld - Wednesday, April 25, 2012 - link

    .... and in this multivariate comparison you choose to ignore the superior battery life which makes Llano a serious competitor in the mobile space. Reply
  • midn8t - Thursday, June 28, 2012 - link

    this the frames pre secound for CPU, you cant really figure out well when gamming its all mostly based around what ever video card they used, in this artical so I would have to guess that they might have used diffrent GPU video card in each system.

    obivuously they cant use same motherboard for amd vs intel

    Also I find it wired that other reciews have Rated the phenom II x6 lower in preformance then the FX chip makes it wired how these review claims that the phenom II which is lower grade CPU is more powerfull then the top of the line AMD product out.
    Reply
  • zeagus - Wednesday, April 25, 2012 - link

    A huge chunk of text is spent explaining how while its a step in the right direction, they need to do more on the GPU side of the equation. Take off your strangely coloured glasses. Reply
  • wingless - Monday, April 23, 2012 - link

    EDIT: I'M NOT KIDDING. I bought my 2600K the Friday before last for $199 and paired it with an ASUS P8Z77-V PRO. Ivy Bridge is simply too hot and lacks OC performance.

    I overclock so I WILL be keeping my 2600K for the foreseeable future!
    Reply
  • fredisdead - Sunday, April 29, 2012 - link

    So HD4000 igp is weaker than last gen Brazos ?? Based on the leaked Trinity benchmarks, Trinity blows any Intel igp into the weeds, never mind the ( already 1.5 yr old ) Brazos, which is 'only' 5% faster. Reply
  • fredisdead - Sunday, April 29, 2012 - link

    So HD4000 igp is weaker than last gen Brazos ?? Based on the leaked Trinity benchmarks, Trinity blows any Intel igp into the weeds, never mind the ( already 1.5 yr old ) Brazos, which is 'only' 5% faster. Reply
  • 1ceTr0n - Monday, April 23, 2012 - link

    I'll keep my 2500k @ 4.6ghz

    Not kidding
    Reply
  • smookyolo - Monday, April 23, 2012 - link

    And I'll keep mine at 4.9GHz.

    But that's just because I'll be waiting for the tock, not the tick.

    I will however be getting a Ivy Bridge Laptop soon.
    Reply
  • Flunk - Monday, April 23, 2012 - link

    Me too, the 2500K is a great chip. Especially with watercooling. Reply
  • Ratman6161 - Monday, April 23, 2012 - link

    For anyone like me who already has a Sandy Bridge quad core (mine's a 2600K) it wouldn't make a lot of sense to "upgrade" to an Ivy bridge. But for those with older systems looking to upgrade, these actually seem like pretty good deals. @ $313 the 3770K is cheaper than the 2700K and cheaper than the typical price on a 2600K (unless like me you are lucky enough to live near a Micro Center).

    As to those complaining about graphics, come on. Will anyone who really cares a lot about graphics, particularly gaming, be using the on board graphics anyway?
    Reply

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