The Thermal Paste Debate Rages On

Written by: Adam Christianson

Categories: Editorial

We have all heard (and even been a part of) the rumors that the MacBook Pros heat issues are stemming from the amount of thermal paste applied. Not too long ago an image was released from Apples service manual that pictured approximately 10-20 times too much thermal grease being applied to the CPU in a MacBook Pro and this was all we were going on. I had my suspicions then that this was simply a pictorial and had nothing to do with the actual amount applied (I still believe any Genius worth their position would not apply, or leave applied, that amount of thermal grease). It would seem however that it is true.

That is to say the amount of thermal grease being applied is far too much, but not that it is making the difference. I just ran across James Duncan Davidsons experiment over at MacDevCenter and it is certainly interesting.

As far as the thermal paste issue is concerned, my opinion at this point is that although the factory’s gooey application may look horrible, it’s probably a perfectly acceptable practice given the factory and service center’s desire to ensure proper contact between the chips and heat pipe with a minimum of fuss. After all, I can tell you that it took much longer to carefully apply the Arctic Silver as instructed than it would have to just glob on the stuff. And if the end result is the same, why not?

James removed the thermal grease from his MacBook Pro as best he could and applied the correct amount of Arctic Silver 5 Thermal Paste which is widely renowned as the best in the business. Otherwise fairly comparing his MacBook Pro with his neighbors untouched yet otherwise identical model showed only a 2ËšF difference both top and bottom of the Macs.

Obviously this is a single case carried out with limited equipment, conditioning and money, and thus is hardly conclusive, but it certainly makes you think there may be less to this whole thermal grease thing than originally thought.

Then again, when the MacCast contacted a representative at Arctic Silver, they more or less confirmed the original theory. They explained thermal grease is designed to fill the microscopic surface imperfections between the CPU and the heatpipe. The heatpipe transfers the heat to the heatsinks and then the fans blow air over the heatsinks to dissipate the heat away from the CPU. According to them you only need a thin almost translucent layer of material to fill those microscopic surface imperfections. In fact, Arctic maintains too thick of an application of grease could act as an insulating layer between the CPU and the heatpipe. Now some will argue that when the MacBook is finally assembled the excess paste is squeezed out hard enough to result in a proper application. No matter what you think it seems the debate will rage on.

Beyond the advantages of efficient heat transfer in cooling James experiment accidentally brought the question of proper airflow into the equation. During reassembly of his MacBook James forgot to re-attach the fan controller (thus it stay on all the time). As a result of the mistake he was able to notice the MacBook remained a lot cooler, even if it did get unbearably loud. So, do we have a second culprit here? Is it back to the drawing board? Can these issues be solved with traditional technologies? Maybe the problem isn’t the technology, but our expectations of it.

We as consumers are constantly pushing for manufacturers to make smaller and smaller notebook computers and they are constantly pushing these boundaries for us. What then is the surprise in that the air cooling system, which relies on space and airflow, is starting to take a hit when confronted with such changes? Perhaps it’s time to invest more in liquid or other such cooling solutions. Either that or stop complaining and embrace our new MacBooks ability to not only encode our latest iMovie project but to also make a nice egg breakfast at the same time.

There are 11 comments on The Thermal Paste Debate Rages On:

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  1. Brian | May 25 2006 - 02:52

    I have had my MacBook Pro 2gHz for about a month now. I will admit that it gets hot, but my experience is that it gets the hottest when plugged into power. While running on battery alone I find that the computer never gets uncomfortable, and dose not feel any hotter to me than the iBook G4 I replaced.

    My feeling is you payed for a rock solid fast laptop. If it fits the bill (and it does) stop whining and be happy with your choice.

    I love my MacBook Pro and a little heat is nothing to complain about. If it starts freezing or otherwise starts acting like a PC then I will complain.

  2. Matt Hoult | May 25 2006 - 02:57

    I agree Brian. There is probably a reason for your noticing the difference. In your System Preferences>Energy Saver>Options do you have Processor Performance on different settings for the different power supplies?

  3. Vic | May 25 2006 - 02:59

    Read somewhere that the latest Firmware upgrade not only fixed other problems, but also does something which made a dramatic decrease in the heat of the MacBook Pros… Sorry, can’t lay my hands on the info about the Firmware upgrade at the moment.

  4. Matt Hoult | May 25 2006 - 02:19

    Yeah, it was an SMC (System Management Control) firmware update so it could be controlling the fans (that’s the rumor) among other things.

  5. Jason | May 25 2006 - 03:30

    All my Dell laptops run hot (where the heat is tranferred to the outside case).

    In fact, the only laptop I’ve ever had that is both quiet and cool is my ThinkPad. I don’t know what they use to keep the heat from transferring to the case, but it sure works well.

  6. maccast | May 25 2006 - 04:43

    You actually want the case to get hot as that means the heat is transfering away from the CPU. I would be worried if I wasn’t feeling heat.


  7. drj | May 25 2006 - 11:46

    I think something to remember is that these machines are meant to dissipate heat, thus their metalic structure/heat cooling pipes/etc.

    I have a new MacBook Pro, and am coming from a TiBook 1Ghz, and a Sony Vaio laptop.

    My thoughts, both the TiBook and Macbook were appreciably hotter than the sony, HOWEVER, the Sony used MUCH more use of the fan/etc. rather than case dissipation.

    I have run the MacBook now on my legs several times (ahh. . sterility. . . here I come) and to my analysis, it’s workable, yes warm, but not 3rd deg. burns. That being said, in before the firmware update, I did have a point when I though I might be getting a 1st/2nd deg. burn on my legs.

    All in all- I’d rather have the sleek & quiet form factor with a bit more heat.

    Paste. . . . hmmmn. . . . Don’t like the idead of extra goop, but I sure as $T#@E% am not going to open up the MacBook to mess with it . . . if it blows up, let Apple fix it, it’s their responsibility.

    My $0.02. GiddyUP!
    Dr. J

  8. Ruth | May 26 2006 - 12:30

    My MacBook Pro gets warm, but nothing to make it uncomfortable on my lap. It’s there now, plugged in to the mains, warm but not hot. Maybe I got lucky, or maybe some people are expecting too much, but I don’t have a problem.

  9. Jason | Jun 09 2006 - 10:25

    Adam, I understand laptops need to dissipate the heat. However, dissipating it through the exhaust vents is much more favorable than the bottom of the case. What I meant was the ThinkPad does a good job of transferring and dissipating the heat through the exhaust instead of the case. This obviously requires more engineering, design, materials, and, therefore, adds to the cost of the unit.

  10. gizli kamera | May 12 2008 - 01:30

    i buyed the one Sony vaio last week. Model no:VGN-FZ31M from Turkey. Here the price About 1900 USD. i don’t know how much is it on the another countriest? who know more cheap price for the model? Anyway i am glad the than PC. it is very fast and very bright screen.

  11. Keith at Quantum Leap Technologies | Jun 22 2008 - 12:48

    Is this still a problem with the new MacBooks? I’ve had a lot of questions about this from customers and not sure what to tell them.

    Best regards,