Creative Communities of the World Forums

The peer to peer support community for media production professionals.

Activity Forums Apple Final Cut Pro Slow rendering – CPU at 85% idle

  • Slow rendering – CPU at 85% idle

    Posted by Bruce Wittman on May 21, 2013 at 7:59 pm

    Hello Cowhands,

    I am looking for some tech heads who can explain my issue.
    FCPX is starting to render very slowly. Urrrrg!
    FYI, I edit all my projects on external 1TB Gtech hard drives.

    So I have been trying all the usual tricks, to no avail.
    Then I looked at the CPU usage while rendering FCPX.

    Look at this picture of my Activity Monitor.

    I am confused by the fact that the CPU usage 85% idle. All the time it is rendering.
    What gives?

    Bruce Wittman
    Executive Producer

    Eagle Video Productions, Inc.
    2201 Woodnell Drive
    Raleigh, NC 27603-5240

    Website: http://www.eaglevideo.com
    Email: br***@********eo.com

    pho: 919-779-7891
    cel: 919-818-5556

    Bruce Wittman replied 12 years, 11 months ago 3 Members · 5 Replies
  • 5 Replies
  • James Cude

    May 21, 2013 at 10:28 pm

    FCPX uses the GPU to render, not the CPU so that’s normal…

  • Mark Dobson

    May 22, 2013 at 6:29 am

    [James Cude] “FCPX uses the GPU to render, not the CPU so that’s normal…”

    And how does the RAM help out?

    Is there an efficiency equation between RAM, GPU and CPU?

    I fitted out my old 2008 MacPro with 22Gbs of Ram and bought the 5770 graphics card and noticed almost no improvement in performance.

    It was only on buying the new 3.4Ghz iMac with 32Gbs of Ram and a NVIDIA GeForce GTX 680MX graphics card that things started to get better, probably as good as they get.

    Export time ( Share ) is now phenomenal and complex renders are also a lot faster.

    I think its important to not underestimate the complexity of whats actually going on under the hood when one is rendering layered full HD clips and the only way to really speed workflow up would be to work with proxies, something I’ve yet to try out.

  • Bruce Wittman

    May 22, 2013 at 12:54 pm

    So how do I see the GPU efficiency? Can I view it like I did with the CPU? Do I need a better card?

    Bruce Wittman
    Executive Producer

    Eagle Video Productions, Inc.
    2201 Woodnell Drive
    Raleigh, NC 27603-5240

    Website: http://www.eaglevideo.com
    Email: bruce@eaglevideo.com

    pho: 919-779-7891
    cel: 919-818-5556

  • James Cude

    May 22, 2013 at 11:43 pm

    What are your system specs?

  • Bruce Wittman

    May 23, 2013 at 12:42 pm

    My 17″ MacBookPro specs are:

    Model Name: MacBook Pro
    Model Identifier: MacBookPro8,3
    Processor Name: Intel Core i7
    Processor Speed: 2.4 GHz
    Number of Processors: 1
    Total Number of Cores: 4
    L2 Cache (per Core): 256 KB
    L3 Cache: 6 MB
    Memory: 16 GB
    Boot ROM Version: MBP81.0047.B27
    SMC Version (system): 1.70f5
    Hardware UUID: 9D90DF9A-FFBF-5B3C-81BA-7881CAEA8E92
    Sudden Motion Sensor:
    State: Enabled

    VIDEO CARD
    AMD Radeon HD 6770M:
    Chipset Model: AMD Radeon HD 6770M
    Type: GPU
    Bus: PCIe
    PCIe Lane Width: x8
    VRAM (Total): 1024 MB
    Vendor: ATI (0x1002)
    Device ID: 0x6740
    Revision ID: 0x0000
    ROM Revision: 113-C0170L-573
    gMux Version: 1.9.24
    EFI Driver Version: 01.00.573

    I have just upgraded my RAM to 16 GB.
    I am curious about upgrading my graphics card
    since I was told the GPU is used for rendering, not the CPU RAM.

    Thanks for any help and insight.

    Bruce Wittman
    Executive Producer

    Eagle Video Productions, Inc.
    2201 Woodnell Drive
    Raleigh, NC 27603-5240

    Website: http://www.eaglevideo.com
    Email: bruce@eaglevideo.com

    pho: 919-779-7891
    cel: 919-818-5556

We use anonymous cookies to give you the best experience we can.
Our Privacy policy | GDPR Policy