How long can/should a MacMini safely stay at full CPU load ?

Discussion in 'Mac mini' started by Full of Win, May 7, 2010.

  1. Full of Win macrumors 68030

    Full of Win

    Joined:
    Nov 22, 2007
    Location:
    Ask Apple
    #1
    So, I’m in the process of converting my movie collection, currently in .dvdmedia containers on an attached HD, to H.264 files for my iPad 3G. Based on the size of the collection, it will at full load/100% CPU use for a month or so cranking 'em out. Depending on the specs of the 4G iPhone, it could take another month or two for those conversions; so I’m looking at keeping the thing on full use for perhaps two or more months.

    So I don’t melt down my laptop, my SOP for rendering is to use a current generation Mac Mini 2.26 GHz model (w/ Apple Care) that I have dedicated to task like this. I keep it raised on a wire-grading shelf so there is plenty of ventilation.

    Part of me does not care if its damaged; the files made go to the attached hard drive, its not a ‘mission critical’ computer, and its under Apple Care. I’m more curious on this, is it possible to damage or destroy a system using it at full load for months?
     
  2. Hellhammer Moderator

    Hellhammer

    Staff Member

    Joined:
    Dec 10, 2008
    Location:
    Finland
    #2
    Heat is never good for components but I'm sure your Mini will be okay, just speed up the fans. If it dies, you have AC covering everything. If I was you, I would build a PC with good CPU and use it solely for that as it sounds like you're doing a lot of it
     
  3. slpdLoad macrumors 6502a

    slpdLoad

    Joined:
    Jun 10, 2009
  4. Full of Win thread starter macrumors 68030

    Full of Win

    Joined:
    Nov 22, 2007
    Location:
    Ask Apple
    #4
    I had thought about doing a Hackintosh, but did not. I use Back To My Mac to manage the Handbreak queue from work or my home office, so I'm kind of locked into the OS X ecosystem for now.
     
  5. wildjohn999 macrumors member

    Joined:
    Feb 12, 2005
    #5
  6. Phantom Gremlin macrumors regular

    Joined:
    Feb 10, 2010
    Location:
    Tualatin, Oregon
    #6
    I don't know about the rest of the system, but Intel takes care to design their CPUs to run at max temperature for many years. The primary failure mechanism at max temp is usually something called electromigration. What this means is that at high temp and high current the atoms constituting the metal interconnect will actually move, or "migrate". This eventually means that piece of metal will fail and your CPU will break. But Intel has very sophisticated tools to analyze this, and they won't allow a CPU into production unless they're confident that the chip can operate many years under those conditions.

    But there's a much worse system problem, and that's when a component (or the entire system) heats up and cools down. This thermal cycling is also very bad for reliability.

    E.g. remember the Nvidia chip failures of a few years ago? Here's a quote from the Nvidia CEO about their problems:

    The flaw, Huang said, was due to the thermal cycling between full-performance and low-power states that notebook chips must endure.

    "This has been a challenging experience for us," Huang added. "However, the lessons we've learned will help us build far more robust products in the future, and become a more valuable system design partner to our customers. As for the present, we have switched production to a more robust die/package material set and are working proactively with our OEM partners to develop system management software that will provide better thermal management to the GPU."
     

Share This Page