Fan issues: slowly we´re getting somewhere!?

Discussion in 'MacBook Air' started by younameit, Mar 9, 2008.

  1. younameit macrumors newbie

    Joined:
    Mar 4, 2008
    #1
    Read almoust all the posts about the heat/fan issues as I want to buy the air.

    It got really interesting after macsimonwoo´s post in the "2nd core shuts down after 30min" thread (THANKS!!):

    "i think it is a known issue that has not been fixed.
    http://youtube.com/watch?v=juZW6eC9rAY&feature=related
    btw, i had this core shutdown too when i viewed youtube full screen..."

    So now it should be easy to analyze if it is a "flash-fullscreen issue", or a general video playback issue (bad cpu design?).
    All we have to do is:
    1. The "no problems with video" crowd should try playing you tube videos fullscreen and check fan speed, etc.
    2. The "My fan breaks speed world records" crowd should play non-flash videos and check......

    I would love to hear that it is "only" a safari-flash bug instead of a bad cpu design.....

    Thanks.
     
  2. clayj macrumors 604

    clayj

    Joined:
    Jan 14, 2005
    Location:
    visiting from downstream
    #2
    Yes, it's a Flash bug. I've noticed a few times that my CPU would heat up and the fans would accelerate to 6200 RPM if I left a Safari window up on the screen that contained a bunch of animated Flash ads. Flash just runs full-tilt boogie and doesn't care that it's pegging the CPU to 100%. (The Arabesque screen saver in Leopard does the same thing.)
     
  3. pgharavi macrumors regular

    pgharavi

    Joined:
    Nov 25, 2004
    #3
    It's not just a flash bug.

    I've had a core shut down while using Skype video chat and many, many times while watching 720p mkv's and standard def. xvids.

    My solution, which has worked 100%, is to make sure the air vent is not blocked. By "blocked" I mean it either hangs of the edge of a desk or you put a decently sized book under the MBA, with the back air vents hanging off, exposed.

    It's like night and day.

    Edit: This is on my second MBA, FWIW.
     
  4. bence8810 macrumors member

    bence8810

    Joined:
    Mar 1, 2008
    Location:
    Tokyo, Japan
    #4
    Hi

    I just tried the Normal size / Full size test on a crappy Dell running XP, and I also get higher rates at Full size. My CPU idles at about 25% on normal size, and jumps up to 80% on Full Size. This is a 1.6GHz Centrino running XP SP2.

    Ben
     
  5. raremage macrumors 6502a

    Joined:
    Nov 21, 2005
    Location:
    Orlando, Florida
    #5
    I've also noticed that the issue seems to resolve if the MBA is elevated to allow better airflow thru the vents. My un-scientific data collection involves watching youtube video while laying on the bed with the MBA propped up on my knees. If the fan starts to spin up, I've adjusted to keep the center of the MBA clear of any obstruction (in this case, the blanket) and after a while the fan slows down - basically, once the CPU has cooled a bit.

    Which leads me to my next hypothesis - someone is gonna make a bundle on desktop stands designed specifically for the MBA.
     
  6. pgharavi macrumors regular

    pgharavi

    Joined:
    Nov 25, 2004
    #6
    I've done the exact same thing and received the exact same result.
     
  7. bence8810 macrumors member

    bence8810

    Joined:
    Mar 1, 2008
    Location:
    Tokyo, Japan
    #7
    But if let's say you have it flat on a tabletop or on your desk, the vents are not blocked right?

    As far as I know, no laptop likes to be sitting on a duvet or even on carpet, where it sinks into the surface and the "legs" cannot lift it away for airflow.

    If the MBA is getting hot even on a tabletop and you need to raise it like with 4 matchboxes, now that would be a dealbreaker. I have mine already ordered and on the way, but I hope it will work on top of a desk, which is where I will use it most of the times.

    Ben
     
  8. pgharavi macrumors regular

    pgharavi

    Joined:
    Nov 25, 2004
    #8
    This is the exact nature of the problem. While sitting on a desk and doing typical work (adium, mail, safari, itunes, and omnioutliner or ms word) the computer WILL warm up to the point where the fans are louder and more consistent than any laptop I have ever owned. There is no 'sluggish' behavior though.

    Once you run video for a while, however, then you get both.

    My vent trick has proven, to me, that it's a heat issue.
     
  9. Tom J macrumors regular

    Joined:
    Sep 15, 2006
    Location:
    Midwest
    #9
    This airflow theory does make some sense. The MacBook Air take-apart photos seem to suggest that the air intake and exhaust areas are only about 4" apart within the single vent in back. If it is sitting on a flat surface, the hot air is exhausted pretty much straight down toward the surface where it is dispersed in other directions INCLUDING back over toward the intake vent where it would suck in the exhausted warm/hot air.
     
  10. teek macrumors member

    teek

    Joined:
    Feb 12, 2008
    Location:
    Norway
    #10
    This is like breathing your own air. Input is oxygen, output is Co2, which flows to the intake again and kills you. In this case, the MBA. hehe.. :)
     
  11. Beliyaal macrumors member

    Joined:
    Feb 14, 2008
    #11
    I have only exprienced one core shutting down while running Parallels or VMWare Fusion. Mostly when I was trying to get them to play videos.

    The CPU gets much warmer when I'm compiling code, and it doesn't shut down then. My guess would be that it's a graphics driver problem and not a problem related to overheating.
     
  12. MRU macrumors demi-god

    MRU

    Joined:
    Aug 23, 2005
    Location:
    Ireland
    #12


    OK I ran the video you linked above on my MBA 1.6 80

    At normal screen with activity monitor open my cpu was at 22%

    At full screen cpu usage went up to 25%

    Both cores were working no problems, and my fans have not become audible and there is no noticeable difference in temperature.

    Obviously not all macbook airs are suffering from thing problem.

    I must mention though that I am running Safari version 3.1 (5525.9) if that would make any difference?
     
  13. younameit thread starter macrumors newbie

    Joined:
    Mar 4, 2008
    #13
    Sounds good. Have your air vents have been blocked?
    Maybe it is really all about blocked vents that cause the heat trouble......which I would still see as a major design bug.
    Hope the air is not a 1,7k table only LAPtop.

    Cheers
     
  14. MRU macrumors demi-god

    MRU

    Joined:
    Aug 23, 2005
    Location:
    Ireland
    #14
    ^ The laptop is on my lap. :)

    Oh and I'm plugged into the charger and power settings are set to 'better energy savings' rather than better performance.
     
  15. younameit thread starter macrumors newbie

    Joined:
    Mar 4, 2008
    #15
    Cool (haha)! I am buying.....as soon as they are available again......

    Thanks a lot!
     
  16. PStamatiou macrumors newbie

    PStamatiou

    Joined:
    Mar 7, 2008
    Location:
    Atlanta/Houston
    #16
    after about 3-4 minutes, my MBA 1.6 went to 1 core 100% usage. But after looking in top safari was only using 25% and kernel_task was using the rest. I've posted about this issue here before and there is a thread about it on Apple but no one seems to have an answer. My cpu was around 63 deg C during this test.
     
  17. MRU macrumors demi-god

    MRU

    Joined:
    Aug 23, 2005
    Location:
    Ireland
    #17
    ^ There's certainly something fruity going on it seems. Fingers crossed it's software and can be rectified via firmware / software update.
     
  18. rom macrumors regular

    Joined:
    Jun 7, 2006
    #18
    I agree! Some folks say that it is QT 7.4.1 and Flash not being compatible. Here's hoping that Apple will issue the patch quickly!
     
  19. mashoutposse macrumors 6502

    Joined:
    Dec 13, 2003
    #19
    Can someone conduct these tests in Windows/Bootcamp?
     
  20. mac jones macrumors 68040

    Joined:
    Apr 6, 2006
    #20
    OK ok

    My fan just got stuck at 6200. Temps were low at 50C.

    It just would not slow down so I put it to sleep then resumed at it was normal

    So there's a problem here.
    :confused:


    What sort of bugs me is if I wasn't a geek constantly monitoring the fan and temps with 'Harware monitor pro' I would not know that the thing is malfunctioning (broken)

    But this sort of thing is easily fixed with an update.

    Apple is going to need to know about this issue.
     
  21. raremage macrumors 6502a

    Joined:
    Nov 21, 2005
    Location:
    Orlando, Florida
    #21
    What I have observed is that my fan doesn't really slow down until the temp gets to about 48 degrees, then it starts a sow descent.

    I have not yet gotten "stuck" at 6200 RPM. I *have* hit it when the temp increases significantly.

    One more thing, I don't see the two extremes only that some seem to (either 2500 or 6200) but a broad range - sometimes I will check and I'm at 3400ish, other times 5600. I have to conclude it is working as designed when I see that. I can watch the temp drop and the fan speed decrease as it cools.
     
  22. mac jones macrumors 68040

    Joined:
    Apr 6, 2006
    #22
    It does seem to eventually (10 minutes) return to normal, and by increasing the air flow under it seems to help a lot.

    I'll just have to wait and see.

    I'm not particularly worried as it's not a temp issue but a sensitve fan issue.
     
  23. bence8810 macrumors member

    bence8810

    Joined:
    Mar 1, 2008
    Location:
    Tokyo, Japan
    #23
    I think there will be a Software fix to this, or some application will pop up that controls the Fans.

    If its a hardware thing though, its a whole different issue. There are people having issues even when on a tabletop, temp increases to the extremes, and it can be resolved only be elevating the bottom of the laptop to allow more airflow. That I guess cannot be solved by software....

    Ben
     
  24. mac jones macrumors 68040

    Joined:
    Apr 6, 2006
    #24
    The thing is sensitive for sure and I think because of the small die size it heats up really quick, and cools down quick also.

    But keeping air flow under it is no problem cuz you have to do that with most if not all notebooks anyway, it's just that this one is a bit more sensitive about it.

    I've reached a sustained 87C though heavy cpu use and didn't get the slowdown/core-shutoff that others have reported. it runs fine at this temp( it seems). But I imagine if I were to block airflow the temps would go through the roof.
    And things would get ugly.
     
  25. MRU macrumors demi-god

    MRU

    Joined:
    Aug 23, 2005
    Location:
    Ireland
    #25
    Well today I am too lazy to go upstairs to the studio to my mac pro so I did some design work whilst watching tv. I had my mac book air on my lap, using photoshop for about 2 hours with a dvd cover at 300dpi with about 30+ layers in the end.

    The fans increased to 3600 rpm, but still not noticeably audible. Processor usage up to 70% average.

    Curtains drawn, screen mid brightness and back lit keyboard on full.

    Charger plugged into the mba, power setting set to 'better energy savings'

    Lacie external 2.5" HDD bus powered drive plugged in.

    At no point did I get a core shutdown, overtly hot temperature or sluggish behavior.


    So it's not all macbooks but it certainly is some.
     

Share This Page