Can Someone Speculate Why SOME MBPs Are Cooler After Updates?

The firmware did very little for me, it still runs hot. After a few ours of gaming, the fans hardly turn on but the bar between the keyboard and screen is very hot to the touch, not warm. I do have the loud electrical whining from somewhere on the motherboard. I also have this problem on my 3 year old IBM Thinkpad with a P3 in it. I blame Intel. 🙂

I'm thinking of running a hard stress test on it soon and see if it'll melt under warranty.

Jean-Cyril,


How difficult was it to open up the MBP and get to the point you could clean the excess compound? I see the screws on the side and bottom of the machine. Once I take them off, how much more work have I got left ?

Thanks

Its actually surprisingly easy. Once the screws are off the Machine (don't forget the two inside the battery compartment towards the front), the keyboard and trackpad assembly comes off fairly easily. Be careful, as the tabs around the keyboard area are quite fragile.. The biggest difficulty I had was after I had removed all the screws from the logic board. It may be abit difficult to pull the display adapter out of the case. I took three hours to take it apart and put it back together, because I basically stopped after every step to check my work. The instructions are generally pretty good, but there were a couple of steps where it was not fully intuitive.

One other suggestion, print out the full set of instructions and scotch tape the relevant screws to the appropriate step as you unistall, so you know which screw goes where. Given the metal case, I highly recommend using a full anti-static pad and ground.

Hopes this helps.

how warm is your left palm rest area after the as5? thats the area that drives me nuts the most

To be honest, it was never hot before that I noticed, but I was really focused on the top bar above the function keys. With the battery installed and charging, and after being on battery-based sleep for five hours, the left palm area is barely warm, not even body warm. It is warmier than the right palm area, which I presume is a ambient temperature. It gets warmer near the magsafe plug, I would say body temperature warm, but not hot.

So your contention is that excessive heat-sink
compound was impeding heat flow? How is that
possible?
Randall Schulz

It is well known that the optimum amount of heat sink compound is the thinnest layer that can be spread evenly between the surfaces. The compound is actually not that efficient at conducting heat -- many times less than metal-to-metal contact -- however to have metal-to-metal would require microscopically polished surfaces. The HSC is there to fill the microscopic air voids between not-perfectly-smooth surfaces, becase the HSC is a better conductor than air.

Too much compound actually causes separation of the metal-to-metal contact, and reduces conduction.

OK. That makes sense.

But if there was excessive compound, wouldn't most of it be outside the junction? You're suggesting that it would in fact constitute material that was holding the two metal component further apart than they could be, but that seems unlikely, too.

Randall Schulz

I followed Jean-Cyril's advice last night and I've noticed a significant decrease in temperature. My MBP is now merely warm under heavy load and the upper surface is actually quite cool under light load. On lap use is now practical for light lifting!

I took photos while it was apart and they're on my fledgling blog at:

http://www.technome.co.uk

(I love iWeb!)

As an engineer of 20 years standing, currently studying for a Nanoscience degree (including thermodynamics), my take on it is this. With a small quantity of compound, all the heat generated by the three chips is transfered directly to the heat pipe by conduction and then the heat pipe is cooled efficiently by the fans. Too much paste will not change the seperation of the dies and pads but will just be squeezed out around the edges. The important thing to realise here is that the paste is a very good thermal conductor so that when too much has been applied a proportion of the generated heat is conducted into the paste that has been squeezed out. Unlike the heat that has been transfered efficiently to the heat pipe, this heat has nowhere to go via conduction but it can radiate into the airspace within the computer and from there, it can heat the exterior of the case by convection.

I have a MBP that has a tendancy to get very hot, So I was quite interested in this topic, especially as it says it's answered.

How is a hack that voids your warranty a solution to the problem of overheating?

Jean-Cyril,

Where are these instruction you refer to?

Thanks

I called Apple this morning and talked to Customer Realtions about this, what I see as a manufacturing defect. He is passing it on to the engineers and hopefully one will be calling me back to chat.

If you are concerned with the factory application of thermal compound and its apparent lack of consistancy across units, CALL APPLE! They love to get feedback on this kind of stuff. If enough concerned owners call, Apple will get the message.

Remember, it's the squeaky wheel that gets the (properly applied thermal) grease!

BB

MBP 2.0 Mac OS X (10.4.6) 1st MBP to Houston twice, may it rest in pieces. Replacement on the way!

I purchased Arctic Silver 5 and Arctic remover plus and cleane r and borrowed #0 screw driver. But I found that I might also need a T6 driver. Do I need a T6 screw driver to take out the logic board to access the three chips?

Yes. A number 00 Philips and a Torx T6 driver are required for disassembly of the MacBook Pro.

Randall Schulz

Sorry, been working at my real job. The instructions are at http://www.ifixit.com/Guide/85.1.0.html.

Randys,

I don't now about everyone else, but most of my compound was in fact outside the junction. I really wish I had taken a picture. Most of it was off the chip completely.

Cal6n actually had more paste on his chips and contact then I did on mine, but I suspect that if we looked at most of those having heat problems, we would find the thermal compound to be the problem.

I really think the MBP is an elegant design/solution, but poor execution will do you in everytime.