Can Someone Speculate Why SOME MBPs Are Cooler After Updates?

Hacking around with 2 grand laptops to fix this issue
is not a solution, they are not fit for purpose.
Return them.

They are advertised and sold as notebooks not laptops.

[)amien


MacBook Pro Mac OS X (10.4.6) 100GB/2GHz/2GB

The only way to test the second fan kicking in is to run the Apple Hardware Test and listen for it.

I have just bought one and its serial No is W861516JVJ0. Its noisy and hot but not at the same time !! Its been on for about 6 hours now and is hot but the whine I can't hear at the moment.

I am very tempted to do the 'remove the excess thermal grease' thing. Its very likely that excess grease is conducting the heat to the wrong place and likely to cause problems longer term. (ex engineer specialising in thermodynamics).

I'll give the store one shot at it - they took a long time to swap a mouse that was dead on arrival and 10 minutes out of the shop.

And here i was thing rev D or E I should be fine !

Finally somebody figured out how to measure the temperature on the CPU. More info over at macrumors forum.

Usually rev letters arent just picked for seperate weeks, more like actual revisions like the speed bumps or whatever

So thats probably why its not fine

My logic board was replaced last week because my machine would not run on battery. The thermal paste application very much resembled all the photos we have seen posted. They are following the procedure in the service manual. I always used the left grill to judge the heat and after Apple's repair it was about the same temperature.

There is a kernel extension available that reports the temperature. Mine new (swapped) machine reports 67 degrees while idling !!
By fixing the grease you probably now need to modify the fan settings as they have probably been set for a thick layer of grease.
Don't know where you would set this but there are some postings about config files where these thresholds are set. Fiddling with them might help. Check postings from cryptonome or the InCrew blog about SpeedIt kext.

Hope this helps.

Hello Folks,
I've been reading every imaginable post related to macbook pro problems and am finally optimistic that there appears to be a genuine solution to the overheating issue.
Jean-Cyril's discovery of sloppily applied thermal paste makes perfect sense as to why the MBP would be running far hotter than it should. It may also explain why "some" MBP's (those with paste properly applied or perhaps improperly if you follow Apple's service manual!) do not experience overheating and why weekly builds W8612, 13, 16, etc. make not one bit of difference. I've really been wanting to buy a Mac notebook now for a few months, but after reading all these posts I've been hesitant. I could care less about "noise" processor, fan, etc., but I do care about things like overheating because excessive heat has the very real potential of damaging internal components (not to mention the LCD display). So, here's what I've decided to do... I will go the Apple Store here in Toronto and tell them that I will buy a new stock MBP 15" 1.83 if the service dept. agrees to remove the improperly applied thermal paste and replace it with Arctic Silver 5.
I will post a follow up and let you know what they say.

iMac 17" 1.83 core duo Mac OS X (10.4.6)

Nice test case. Keep us posted. I'm very curious as to the outcome of your mission 🙂

Hello Everyone,
I had an opportunity to visit the Apple store here in Toronto and quickly made an appointment to see a Mac "genius".
All I wanted to ask is simply the following:

"If I purchase a MacBook Pro in the next few days and find
that after using it that it gets uncomfortably hot (say in excess of 45C), would an Apple certified technician clean the excess thermal paste off of the CPU, GPU, and Northbridge?"

He stated that servicing the MacBook pro for heat related issues currently includes adressing the chip components, thermal sensors, and thermal paste!
He spoke in a mannner that led me to believe that service techs are very aware of the excess thermal paste issue on MBP's.
So I asked specifically if I (or Apple) could, before shipping the MBP for servicing, include a note specifically requesting that the thermal paste be removed, the chips/pipes cleaned, and new thermal paste (Arctic Silver 5) be reapplied according to the guidelines on the arctic silver website:
http://www.arcticsilver.com/arcticsilverinstructions.htm

He stated that he wasn't absolutely sure (because he didn't have the authority to make that decision) but that he "didn't see why that would be a problem at all"!
He said that I would have to ask the store manager to be absolutely sure.
I asked if I could speak to the manager and he said "of course", but the manager wasn't available at that moment.
I must acknowledge that the "genius" I spoke with was very kind, helpful, and accomodating.

So I left telling him that I would return in a few days, get confirmation from the manager, and if they could assure me that my request to replace the thermal compound by Apple service techs would be honoured, that I would agree to purchase a MBP at that time.
So, all in all, it sounds very promising that if I buy a MBP with a weekly build number of W8616... or later that I would be guaranteed either an acceptably "warm" (not HOT) system or else have the problem immediately addressed by Apple techs (at no cost to me (except for the Arctic Silver 5 of course), and more importantly, WITHOUT voiding my warranty)!

I hope the manager agrees on Tuesday, and I will keep everyone posted.


iMac 17" 1.83 core duo Mac OS X (10.4.6)

Well, I also upgraded my drive from 5400 to 7200 RPM.

I am waiting for my 17 inch 2.16 MBP and I upgraded my HD to the 7200rpm . Does anyone think this will create an even more heat problem with the themal grease thing. Also someoone mentioned thermal pads is there any companies out there that sell them that I (we) could either apply or cut to size over the grease I would assume . Maybe some mac geek can think of a way to make and apply a therml pad

OK, I just can't resist jumping in. My qualifications are that I have been a fizzycist, working in thermal conductivity (although stressing insulation) and am also a computer nut.
I also get a kick out of numbering my points:

1. The amount of heat coming out of a chip under IDENTICAL internal conditions will be dissapated into the outside world somewhere. The amount of heat going out of the chip and therefore heating the air and the case together will not be any lower if you interfere with the thermal path to make the chip itself hotter. So, if the case and air both seem cooler after the "fix" and the computer runs applications just as well, then you have not done anything wrong.

2. If the chip gets hot enough to trigger both the fans and the power management (chip internal clock speed, etc.) then the power generated will be less and everything will be cooler except the chip. But your computer will be slower and the chip life will probably be reduced.

3. If the chip gets hotter because of a poor thermal path, then it is very likely that the amount of power generated inside the chip will (other things being equal) be greater than for a properly functioning chip. Since that heat must go somewhere, the computer will end up dissapating more heat to the outside world and is likely to feel hotter.

4. Firmware and software changes can, since this is a dual core chip, change whether the second core is active for a given level of required processor power. Shutting off the second core completely when the processor load is low enough can reduce the heat generation significantly. And it may not have any noticeable effect on benchmark speed for that type of use. But you may only notice the reduced temperature when you are in the load envelope in which the strategy has been changed.

5. Resetting the PMU: Not sure at all what is happening here, but most likely the power conserving tools available by managing the chip as well as the control of the fans may be less than optimal for some reason.

In summary, all of the conflicting observations above are possible and not necessarily really conflicting. And most of you are right, except when you are wrong.

End of rant.

17" Aluminum PB Mac OS X (10.4.5)

I updated the heck out of it. My MBP is so hot that I cant touch the bottom for more than five seconds. I have tried to stand it longer...but I felt like that dude on Dune when he had his hand in the Bene Gesserit Witch's box and was trying to withstand the burning pain to his hand. Yes, it sits on a hard surface. I am measuring the temp right now...but it is quite awkward using a meat thermometer. That being that it's round and the first readable temp starts at 140. It is slowly creeping up to that. I would bet it reaches 180. Any takers? And Apple says that an acceptable HOT operating temperature is 120.

Well, it's pushing 160 and I cant watch it any longer. zzzzzzz
It will be interesting to see the temp in the morning...after it sits all night doing nothing.

I will buy a reliable flat thermometer tomorrow. Or better yet, maybe I'll take my blazing hot MBP to the brand new Apple Store that is only 5 minutes from my house!

I can only surmise that the problem does lie with the poor application of thermal grease. The fact that peoples fans run more often or are more noticeable after reapplication of the grease only serves to back this up.

If you think about it, once you improve the rate of heat transfer between the core and the heatpipe, the heatpipe heats up quicker, the temperature sensor for the fan controller is on the heatpipe so the fans turn on faster as well.

If there is poor conductivity between the heatpipe and the core, the heat will be dissipated through convection in the case or through the motherboard as opposed to through the heatpipe.

This is supported by the fact that i have a new core 2 duo macbook and the fan is only ever noticeable or loud when when the cpu is running at 78C that's pretty **** hot! This is when i rip a cd in iTunes which isn't using 100% cpu but more like 75%. Usually, a fan would be kicking in at half that temperature so it is cause for concern.