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.