MacBook Pro Over Heat Issue

Discussion in 'MacBook Pro' started by macbrain2010, Mar 9, 2010.

  1. macbrain2010 macrumors newbie

    Joined:
    Jan 7, 2010
    #1
    Dear All,

    Have a nice day, May I know

    1. What is normal working temperature of MacBook Pro late 2009?

    2. What can be the maximum temperature ?

    3. When one should really worried about its machine temperature?

    4. My system temperature is 62 when CPU usage is 5% and it goes to 82-90 degree C when CPU usage reach 54% to 70% is this normal and expected ?
     
  2. miles01110 macrumors Core

    miles01110

    Joined:
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    Location:
    The Ivory Tower (I'm not coming down)
    #2
    1. varies between 40 and 100 C depending on usage.

    2. Around 100 C.

    3. > 100 C

    4. Normal.
     
  3. Pax macrumors 6502a

    Joined:
    Dec 12, 2003
    #3
    +1

    The Intel spec says 105 C not 100 C so you might see that number sometimes. The fan control algorithm seems to let it go to 105 C for a short while, and then it brings it down to 90 - 95 C.

    Don't worry about it, the temperatures seem high but they won't damage the CPU.
     
  4. ouimetnick macrumors 68020

    ouimetnick

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    Aug 28, 2008
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    Beverly, Massachusetts
    #4
    Yes, but the temp can damage other components on the logic board.
     
  5. Ice Dragon macrumors 6502a

    Ice Dragon

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    Jun 16, 2009
    #5
    There was a fan thing to put under the MBP I believe that you can plug in. How does that decrease the temperature?
     
  6. Caris macrumors 6502a

    Caris

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    Location:
    Newcastle Upon Tyne, UK
    #6
    Cools the bottom of your laptop, decreasing internal temperatures.
     
  7. Michael CM1 macrumors 603

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    Feb 4, 2008
    #7
    I'm having an issue as well, although it's with an early 2007 model. Last year and before, I used HandBrake from time to time. Even with it using almost every drop of CPU power, the temperature never topped 185, 186 F. I haven't used HandBrake as much recently because I've been having problems with lockups and the software actually working.

    Well I finally figured out how to get it working again and have tried to use it this weekend. My computer has been locking up still, and I noticed one time that the temperature was getting up to 194 degrees, maybe even higher. I tried opening the display -- I normally use clamshell mode -- and made the room temperature a little cooler. It still jumps back up into that range after a bit. I've got a cooling fan under the computer and everything.

    So basically I wonder if something is whack. I'm using 32-bit HandBrake, FairMount and VLC with Snow Leopard. The skeptical part of me wonders if it's Snow Leopard since I know it runs things differently than Leopard. I thought my hard disk may have been screwy to cause the lockups, but now I'm thinking maybe it's something else.

    So if anybody has advice, I'd love it. Thanks!
     
  8. Pax macrumors 6502a

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    Dec 12, 2003
    #8
    Evidence please?
     
  9. Pax macrumors 6502a

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    Dec 12, 2003
    #9
    You need to find out what CPU you have and then look it up on the Intel site. Almost all the CoreDuos and Core2Duos have a temperatures threshold of 105 C. But one base model had a threshold of 90 C, I can't remember which one.

    Above this threshold the CPU will throttle its clockspeed, but not shut down. Above this threshold + 20 C (IIRC) the CPU will shut down.

    If your CPU is too hot you should see a slowdown, but not a lockup
    If your CPU is CRAZY hot your Mac should shut down completely ie black screen

    So I doubt the CPU temp is the problem

    It's possible your RAM is bad, try reseating it. Also run the Hardware Test suite and/or try booting from a DVD etc etc. All the usual diagnostic stuff.
     
  10. abs1nthe macrumors member

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    Mar 14, 2010
    #10
    heat spreads. excess heat kills electronics.

    duh?
     
  11. Pax macrumors 6502a

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    Dec 12, 2003
    #11
    Nice idea, but not the kind of heat we are talking about.

    The components on your logic board are specced to 80 C

    The die is at 105 C, the heatsink is in direct metal-to-metal contact with the die and is only at 80 C

    The other components get heat from the die via a ceramic chip carrier (poor conductor) and the PCB itself (very poor conductor) or via convection (very poor heat transfer) from the heat pipes which are carefully designed to run above the PCB to not heat it.

    The other components are heated to nowhere near 80 C. For example on my MBP the Northbridge never goes over 55 C. That's nothing compared with the 80 C spec.

    My evidence shows that even with the CPU at 105 C the other components are so far inside their temperature specification that it won't be a dominant failure mechanism. Other factors will limit the mean time between failures of your logic board.

    My point is, please provide evidence that running your CPU to 105 C causes other components to go out of specification (80 C) thereby making temperature induced failure dominate the MTBF of the logic board.

    Oh, and, Duh
     
  12. abs1nthe macrumors member

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    Mar 14, 2010
    #12
    If the MBPs design is so magical that the heat transfer is somehow contained to ONLY go between the chip's IHS and the heatsink, then yes this would make sense. I think it's reasonable to acknowledge that excess heat (especially in the case of crazy high overheating) can permeate this contact, and go into the air inside the chassis, spreading around to every other component of the system. I know for a fact that the hotter my CPU gets, the hotter the ambient temp in my case gets. And my desktop PC has a MUCH better heatsink, MUCH better airflow, and obviously MUCH more room for heat dissipation than a cramped MBP. Reasonably though, the chip would die and the system would turn off long before the ambient temp rose enough to damage other components, but if, theoretically, the chip could be run at 125 C (this is the shut down threshold, i think) without failure/shutoff for a significant amount of time, that's exactly what would happen. The post you originally quoted said that high temps CAN damage other components.

    EDIT: and to reiterate, he didn't make the claim that a CPU running at 105 C WILL MOST CERTAINLY kill the logic board, he said "the temp can damage other components". I assume he was alluding to what I said, that heat spreads and, in excess, can damage electronics.
     
  13. Pax macrumors 6502a

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    Dec 12, 2003
    #13
    Yes of course a hot die makes the inside of the case hot and therefore and the components within it. But the important questions are
    1 - how hot?
    2 - does it matter?

    In my previous reply I showed that the answer to 1 is "not very" and 2 is "no"

    If you want to post an alternative argument using specification limits of key components and failure mode analysis, I'd be interested to hear it.
     
  14. abs1nthe macrumors member

    Joined:
    Mar 14, 2010
    #14
    that wouldn't be necessary because my initial post was in response to something that I thought was obvious; that is, ouimetnick's comment that heat can damage other components. you demanded evidence of this, i'm guessing, because you thought he specifically meant "a MBP's C2D running at 105 C for any period of time is guaranteed to kill the logic board". If that IS what he actually meant, then my comment was unnecessary and has no place in this discussion, and I'd agree with you and similarly request evidence of this statement. But if he WAS just making the general statement that an overheating CPU has the possibility to damage surrounding components, whatever the exact circumstances may be, then we are both correct in our arguments and there's no need to dispute anything. Either way, I probably shouldn't have has jumped to conclusions in my interpretation and made it sound like I thought your response was stupid. Sorry to hijack this thread. :)
     
  15. Pax macrumors 6502a

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    Dec 12, 2003
    #15
    @ abs1the

    Yep I take your point, fair enough.

    What I was trying to get across is

    - people shouldn't worry about the die temperature on their Mac. It's not going to damage it or shorten its useful life

    - IMHO the coolpads etc that people buy for serious money are simply snake oil. They solve a problem which doesn't really exist - premature Mac death through logic board overheating

    (
    If I wanted to be really nitpicky I'd say that ouimetnick said "the temp can damage other components" and in context that meant the 105 C vs 100 C of the die. This was what I disagreed with and wanted evidence for. I believe that ouimetnick's comment reinforced the overheating myth which supports the "snake oil" coolpad market and leads to dozens of "OMG my Mac is sooooooo hot" threads on here.

    105 C vs 100 C will make no material difference to the other components which will be perfectly happy at either, and neither temp will materially shorten the useful life of your Mac
    )

    cheers
     
  16. Ice Dragon macrumors 6502a

    Ice Dragon

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    Jun 16, 2009
    #16
    Thank you for replying. I should have included "by how much?" so my fault there. I know some may not have issues but the device I speak of... can it keep my MBP at 40-60 degrees Celsius if running consistently.
     
  17. Pax macrumors 6502a

    Joined:
    Dec 12, 2003
    #17
    No

    The bottom of the MBP does not get very hot and so cannot be used to cool the Mac significantly.

    I ran mine at 100% CPU for 20 minutes on a hard wooden table. The CPU settled at 95 C, the heatsink at 75 C. But the enclosure bottom never got above 31 C.

    Almost no heat is lost through the enclosure bottom. It all goes out through the vents. A coolpad won't make any significant difference. I expect it could make 3-5 C difference.

    It will not cool your CPU to anything like 40 C.

    To be honest I really, really would not worry about your CPU temperature. It is not going to kill your Mac.
     
  18. Ice Dragon macrumors 6502a

    Ice Dragon

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    Jun 16, 2009
  19. Michael CM1 macrumors 603

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    Feb 4, 2008
    #19
    Thanks for the info. I'll try reseating the RAM. I guess the latter stuff means I'll have to actually find my Snow Leopard DVD. That's always fun.
     
  20. Pax macrumors 6502a

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    Dec 12, 2003
    #20
    Behind the sofa? In a DVD box? dropped behind the printer? That's where mine usually are :)
     
  21. ouimetnick macrumors 68020

    ouimetnick

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    Location:
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    #21
    Yes it can. The CPU can handle the temps, but other chips may have a reduced life span due to the increased heat.
     
  22. vant macrumors 65816

    Joined:
    Jul 1, 2009
    #22
    Heat will always shorten the life of any chip.

    A processor stable at 40c will last longer than one at 50c. Both of which would last far longer than one stable at 70c.

    Temperatures exceeding the threshold will invoke immediate failure.

    Best bet? Keep it as low as possible.
     
  23. ouimetnick macrumors 68020

    ouimetnick

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    Aug 28, 2008
    Location:
    Beverly, Massachusetts
    #23
    Thats why i'm glad My Dell has a nice heatsink on it. My laptop heats up to 120F under full load, and ideals at 90F.
     
  24. Pax macrumors 6502a

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    Dec 12, 2003
    #24
    Not true. Below a certain temperature the dominant failure mode will not be heat related. In this situation changing the temperature will not affect the lifespan. For example if 95% of chips fail because of manufacturing defects in the solder (like the nVidia GPUs), changing the temperature of the chip will do damn all to its average lifespan.

    Not true & hilarious. Exceeding the temperature threshold will change the electrical properties to the point where the manufacturer can't guarantee the performance. For a CPU the timing and leakage will be wrong to the point where the chip might "crash" but it won't fail. Intel shuts the chip down at 125 C mostly because its critical timings will be very wrong, and also because 125 C is indicative of a horrible cooling system failure which might make the chip even hotter. Remember during soldering the chip gets up to 200 C + without any damage.
     
  25. Pax macrumors 6502a

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    Dec 12, 2003
    #25
    Once again, please show me some evidence please that heat death is a dominant failure mode for SMT components running at 55 C.

    I would be happy to discuss facts and evidence on this, but we keep going round and round the "heat kills Macs ooohhhh yes it does" argument without any data.

    My position is clear, and I'd like to discuss it with a real expert (I'm not) who can refute some of my arguments with hard data
    - the interior of your Mac never gets above 55 C
    - that kind of temperature will not cause temperature related failure to become the dominant failure mode of your components
    - therefore temperature will not materially affect the lifespan of the components or your logic board

    15% of Macs fail after 3 years. The vast majority fail because of non-logic board related issues. I expect 1-2% have logic board failure. Most of that 1-2% will not be heat related because heat is not the dominant failure mode. By worrying so much about cooking your Mac you are worrying about something that ain't gonna happen. By all means do it, but don't pretend to other people that it's really really important.
     

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