macbook pro, CPU pegged, lid closed ... comments ?

Discussion in 'MacBook Pro' started by gjarold, Feb 10, 2008.

  1. gjarold macrumors regular

    Nov 14, 2007
    I am thinking of running some video demos off of my macbook pro.

    It is a newer 15" 2.6 ghz core2duo.

    The video in question will be h.264 running at a fairly high bitrate using VLC. The point is, the CPU will be fairly pegged.

    So my question is, how will the computer behave if I put this workload on it, for hours at a time, and close the lid ? Two specific questions:

    - will the fan run extremely loud ?

    - any danger of overheating / problems ?

    Has anyone done this - perhaps watching a blu-ray rip while attached to a TV or something like that ?

    Comments ?
  2. gjarold thread starter macrumors regular

    Nov 14, 2007
    one other note - I have heard that macbook pros actually use the keyboard to dissipate heat - but I also read that that is not true anymore, and that heat is no longer dissipated via the keyboard.

    Can anyone clear this up ? If macbook pros no longer dissipate heat via the keyboard, what model revision did they cease this practice ?

  3. cmm26red macrumors regular

    Jan 29, 2008

    Wouldn't the video card take this task?

    NVIDIA PureVideo® HD Technology 2
    Dedicated on-chip video processor
    High-definition H.264, VC-1, MPEG2 and WMV9 decode acceleration
    Advanced spatial-temporal de-interlacing
    HDCP capable 3
    Noise Reduction
    Edge Enhancement
    Bad Edit Correction
    Inverse telecine (2:2 and 3:2 pull-down correction)
    High-quality scaling
    Video color correction
    Microsoft® Video Mixing Renderer (VMR) support
  4. bmcgrath macrumors 65816


    Oct 5, 2006
    London, United Kingdom
    Well the way I see it is, the Macbook Pro is "designed" to run with the lid closed (clamshell mode) There should be no risk doing this.
    On the other hand perhaps just to save you from running into an overheating problem, just leave the lid open while playing these videos.
  5. Crow47 macrumors member

    Feb 6, 2008
    Regardless whether it's open or closed, the fan is probably gonna run a bit loud.
  6. taylorwilsdon macrumors 68000


    Nov 16, 2006
    Bay Area
    I wouldn't subject my machine to that. If I were you, I'd pick up some sort of desktop cooling pad (around $25) that runs off a USB power draw to the laptop, and then I would install SMCFanControl and crank them most of the way up to minimize the heat.

    It might run right now, but subjecting the components to high heat over long periods of time is going to reduce the longevity of the computer.
  7. Shannighan macrumors 6502a


    Jul 26, 2007
    Buffalo, NY
    im guessing with the lid closed its going to run louder with normal because the screen is going to ask as an insulator and trap more heat (not alot but enough to kick the fans in high gear. the laptop open a crack so some air can come in through the keyboard.

    i dont see why your laptop would have a problem displaying those videos though
  8. gjarold thread starter macrumors regular

    Nov 14, 2007
    (just because the video card has that hardware in it doesn't mean that the software, in this case, VLC, is optimized to utilize it ... running 20mbps h.264 is going to use a ton of CPU ...)

    Ok, thanks. SO whenever they stopped running the cooling _through_ the keyboard, it was prior to the current generation of macbooks, so I shouldn't need to worry about squelching the airflow by closing the lid ?

    We'll see how loud the fan gets.... thanks!
  9. DocSmitty macrumors regular

    Jan 7, 2008
    Lincoln, NE
    I'm not sure that they ever intentionally used the keyboard to dissipate heat. The earlier models had thermal paste issues that prevented the heat spreader on the bottom of the notebook from picking it up efficiently, meaning the top case of the notebook would often become very hot. That info extends back to the first MBP revisions. Prior to that (Powerbook) I'm not sure how they handled heat.
  10. george.argueta macrumors newbie

    Feb 24, 2008
    Mac book pro, lid closed mode doesn't work with a HDTV


    I have a Sony HDTV that comes with a VGA built in cable, when I plug it in my Dvia to VGA converter in my Mac Book Pro, the close lid mode doesn't work if i go thru the instructions in Supoort in the site.

    Does anyone has had this problem, by the way i'm using a bluetooth keyboard and mouse
  11. e12a macrumors 68000


    Oct 28, 2006
    there should be no risk and technically it should be able to handle it as others have mentioned the clamshell mode.

    and it is true that they no longer use the keyboard. if you look underneath the keyboard/top case there is a black film underneath that would negate any cooling effect through the keyboard.

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