MacBook Pro 15 slow encoding - faulty?

Discussion in 'MacBook Pro' started by Donka, May 21, 2015.

  1. Donka macrumors 68020

    Donka

    Joined:
    May 3, 2011
    Location:
    Scotland
    #1
    Okay, so I recently picked up a Mid 2014 rMBP 15 base model with i7 2.5Ghz/16GB/512GB/Iris Pro.
    It's a great machine although I did notice right from using it that the fans are always audible, even when idling, albeit quietly. I came from a rMBP 13 and you could never hear the fans apart from when loaded.
    The issue I face is when rendering or encoding video. I am encoding ~ 10 min 1080p clips in Handbrake and it will sometimes start around 200fps but slow down as the fans ramp up and it often stays around 70fps with the occasional spike up to around 100/110fps. My rMBP 13 would never drop below 100fps with the same clips and when I test my Mac Mini i7 2.3Ghz/16GB/480GB SSD using the same clips, it fluctuates between 110 - 170fps with a average ~145fps.

    Does this sound like I have a cooling issue with the rMBP 15 when both the rMBP 13 and Mac Mini appear to out perform it? Video editing is one of the main reasons for the upgrade to the rMBP 15 so this is a real concern.
     
  2. Samuelsan2001 macrumors 603

    Joined:
    Oct 24, 2013
    #2
    Yep that sounds like it is throttling back it should be a lot faster than the 13 or the mini.....
     
  3. Donka thread starter macrumors 68020

    Donka

    Joined:
    May 3, 2011
    Location:
    Scotland
    #3
    Any easy way to diagnose? I installed iStat Menus this morning and checked it on idle and the fans are running around 2000rpm with cpu temps around 28-30oC. I'll test it tonight under load. Is there a tool that will show the current cpu frequency?
     
  4. Wahlstrm macrumors 6502a

    Wahlstrm

    Joined:
    Dec 4, 2013
    #4
    The 13" should be far behind and it should at least be on par with the mini, they have about the same performance in geek bench. (2,3 i7 2012?)

    The mini has better cooling so for long periods of heavy load I think the mini still have an edge when it comes to running the CPU at full speed.
     
  5. Donka thread starter macrumors 68020

    Donka

    Joined:
    May 3, 2011
    Location:
    Scotland
    #5
    Yes, the mini is 2012 2.3 i7. At it's fastest, the 15 is a good bit quicker than the 13 but for most of the time, the 15 is sitting at a low encoding speed which is my main concern. I just found Intel Power Gadget to test the cpu frequency so I'll do some testing tonight to see how quickly the 15 appears to throttle and to what speed.
     
  6. Donka thread starter macrumors 68020

    Donka

    Joined:
    May 3, 2011
    Location:
    Scotland
    #6
    Okay, I've tried the test mentioned in the following thread and averaged just over 70fps. It looks like things are actually performing as expected. Can anyone else with a similar spec rMBP confirm they get similar fps?

    http://forums.macrumors.com/showthread.php?t=1111126
     
  7. Crzyrio macrumors 65816

    Joined:
    Jul 6, 2010
    #7
    Will give it a go when at home.

    Try manually turning up the fan speeds to max before starting the conversion and make sure its on a table. It might just be throttling due to the heat.
     
  8. Donka thread starter macrumors 68020

    Donka

    Joined:
    May 3, 2011
    Location:
    Scotland
    #8
    Thanks. I did monitor the system, fans ramped up to ~6000rpm and CPU temps were ~98oC. CPU frequency fluctuated a good bit but averaged ~3Ghz. After the encoding was complete, the fans quickly eased off and CPU temps dropped below 40oC. Idling before the encoding saw temps of ~30oC. I suspect the throttling I saw was normal as is the encode speed. I don't have the 13 anymore to compare again but I must have used SD material previously.
    It would be good if someone with a similar spec could confirm around 70fps average with the same test.
     

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