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Ivy Bridge Running Hotter Than Intel's Last-gen CPU

Posted by Soulskill on from the water-under-the-bridge dept.

crookedvulture writes "The launch of Intel's Ivy Bridge CPUs made headlines earlier this week, but the next-gen processor's story is still being told. When overclocked, Ivy Bridge runs as much as 20C hotter than its Sandy Bridge predecessor at the same speed, despite the fact that the two chips have comparable power consumption. There are several reasons for these toasty tendencies. The new 22-nm process used to fabricate the CPU produces a smaller die with less surface area to dissipate heat. Intel has changed the thermal interface material between the CPU die and its heat spreader. Ivy also requires a much bigger step up in voltage to hit the same speeds as Sandy Bridge."

13 of 182 comments (clear)

  1. Good! by Kenja · · Score: 4, Funny

    After switching all my lights to LED bulbs, its a bit cold in my office. A new, hotter CPU could be just what I need.

    --

    "Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
    1. Re:Good! by vjoel · · Score: 5, Funny

      That's twenty degrees celsius, which is quite warm where I'm from.

      That's twenty degrees of *WOOSH*, which is quite embarrassing where I'm from. ;)

      --
      What part of `yes no` don't you understand?
  2. notice the "when overclocked" caveat by Trepidity · · Score: 5, Informative

    It's clear in the article, but the headline here sort of implies that the chips run hotter in general, whereas this test is only saying the new chips run hotter when overclocked. From what I can find, when run at the rated voltages/speeds, Ivy Bridge CPUs run at about the same temperature as last gen's CPUs.

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    10 PRINT CHR$(205.5+RND(1)); : GOTO 10
    1. Re:notice the "when overclocked" caveat by Alastor187 · · Score: 5, Informative

      It's clear in the article, but the headline here sort of implies that the chips run hotter in general, whereas this test is only saying the new chips run hotter when overclocked. From what I can find, when run at the rated voltages/speeds, Ivy Bridge CPUs run at about the same temperature as last gen's CPUs.

      Seems like that would make sense if at normal 'voltage/speed' the Ivy Bridge is using less power. Based on the the numbers in the link the Ivy Bridge has a higher overall thermal resistance, junction-to-air, of roughly 30% [=((100C-20C)/(80C-20C))*(231W/236W)]. Based on other reviews the Ivy Bridge processors uses less power at stock frequency/voltage so that may be offsetting much of the temperature rise due to an increase in package resistance and heatsink interface resistance, under normal conditions.

      Power dissipation increases exponential with increases in frequency/voltage and it appears to rise faster with the Ivy Bridge processors. So as the power dissipation approaches or exceeds that of the Sandy Bridge processor much higher processor temperatures will be measured in the Ivy Bridge because of the higher thermal resistances.

      I think this is a non-issue for the average consumer. However, overclockers would probably be better off with the Sandy Bridge hardware.

    2. Re:notice the "when overclocked" caveat by tommasorepetti · · Score: 5, Interesting

      Completely agree. The overclocking community is somewhat overrepresented in reviews of computer hardware. Overclockers are, in general, very knowledgable, so I am not saying that their voices as part of the reception are a problem--it is, after all, often overclockers who push the limits of current generation architectures and empower consumers. It is important to note, however, that thermal issues when overclocked are secondary to efficiency and power consumption for well over 99% of all computing applications. I work in HPC and obviously care about eeking out performance from my platforms, but I have never overclocked a CPU. A modest performance increase is completely secondary to jeopardizing the reliability of a computer system. As far as I am concerned, this particular critique is irrelevant, and I think that many other lay people and professionals would feel the same way. I am much more interested in knowing if the logevity of the new chips is commensurate with that of the previous generation.

    3. Re:notice the "when overclocked" caveat by Anthony+Mouse · · Score: 4, Interesting

      This is true as far as it goes, but the behavior when overclocked is telling for more than how well you can overclock: At the risk of stating the obvious, the chips the overclockers are having heat issues with are the ones Intel is manufacturing. That means Intel isn't going to be able to ramp the clock speed very easily for the same reasons that the overclockers are running into trouble, unless there is some significant and avoidable flaw in the chip or the process that they can remove in future revisions.

      On the plus side, this gives AMD a little breathing room to try to catch up a little.

    4. Re:notice the "when overclocked" caveat by spire3661 · · Score: 4, Insightful

      Overclocking had its day back when the Celeron 300A was out. Now its all poseurs OCing to get a few more framerates and burning out their CPUs. Very VERY few of them OC it for anything more then penis. Sure you'll get some folding guys or dudes running triple 4k monitors. When I OC'd back in the day it was so i could MOVE faster in Quake 3, not so i could post benchmarks. Overclocking should be used to reach a performance level you couldn't otherwise get with money.

      --
      Good-bye
    5. Re:notice the "when overclocked" caveat by Mattsson · · Score: 4, Insightful

      Also, if a large part of the reason why the Ivy Bridge CPU runs hotter is the smaller area of the chip and the changed thermal interface materials, this means that while the new CPU chip might run hotter than the previous one, it doesn't put out more heat.
      The CPU is hotter but the heat sink is cooler since the energy can't be transferred from the chip to the heat sink fast enough.
      If this is the case, then Intel need to do something about the CPU package before going to higher frequencies.
      It also means that people needing the extra heat in their cold rooms would be disappointed since the heat output would be lower, not higher. ;-)

      --
      /.Mattsson - My native language is not English, so please don't whine over linguistic errors. (That's lame anyway...)
  3. 3d tri-gate not as good as promised by edxwelch · · Score: 4, Interesting

    Remember a year ago Intel was bragging about their new 3d tri-gate process would be 50% more power efficient: http://www.intel.com/content/www/us/en/silicon-innovations/standards-22nm-3d-tri-gate-transistors-presentation.html.
    Comparing the i7 3770K against the 2600K, which is clocked at the same frequency it's only 17% more power efficient: http://www.anandtech.com/show/5771/the-intel-ivy-bridge-core-i7-3770k-review/20
    Also you have to bare in mind some of the power saving is due to the DDR controller power gating

    1. Re:3d tri-gate not as good as promised by gstrickler · · Score: 5, Informative

      Read the Anandtech review, that's total system power consumption. If you compare just the CPU power consumption it's ~33% more power efficient (66W increase from idle to load for Ivy Bridge vs 98W increase for SB). And if you look at the GPU intensive comparisons, IB is ~20% more power efficient, but that's including a ~33% increase in GPU cores and an increase in GPU clock, for an ~40% increase in performance while using 20% less power. For the first generation chips on a brand new production process, those are very good results. I expect to see them improve as their 22nm tri-gate process matures.

      --
      make imaginary.friends COUNT=100 VISIBLE=false
  4. Subject needs "overclocking" by ganjaganja · · Score: 5, Insightful

    Not all of us do overclocking. Subject is misleading.

  5. You're slipping, intel. by game+kid · · Score: 4, Interesting

    So lemme see here...Intel's new CPU dies are now smaller (good), which makes them less dissipative of heat (bad), so they decide to use worse thermal paste stuff?

    Seems legit.

    --
    You can hold down the "B" button for continuous firing.
  6. Hotter != more heat by Ken_g6 · · Score: 5, Informative

    After switching all my lights to LED bulbs, its a bit cold in my office. A new, hotter CPU could be just what I need.

    You're confusing temperature and heat. A candle burns hotter than a person, but a person puts out more heat (100W) than a candle (80W). Likewise, Ivy Bridge puts out less heat than Sandy Bridge, even though it's hotter.

    --
    (T>t && O(n)--) == sqrt(666)