Macbook: Adjustment of CPU speed possible?

Discussion in 'MacBook' started by mayuka, Feb 23, 2009.

  1. mayuka macrumors 6502a

    mayuka

    Joined:
    Feb 15, 2009
    #1
    Hello everyone.

    I just upgraded from an old iBook G4 to a shiny new Macbook. On my old iBook I could adjust the cpu speed to a lower value to get a longer battery life (only about 20 minutes though) and/or a lower fan speed. On my new Macbook these preferences vanished from the "energy saver" options dialogue in the System Preferences. How can I enable them? Are the CHUD tools maybe of interest?

    Thanks!
     
  2. r.j.s Moderator emeritus

    r.j.s

    Joined:
    Mar 7, 2007
    Location:
    Texas
    #2
    What do you have under Optimization?
     

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  3. mayuka thread starter macrumors 6502a

    mayuka

    Joined:
    Feb 15, 2009
    #3
    Nothing more. But on the iBook I had the choice of the processor speed between "low", "medium", "high" speed... This entry seems to be gone also from the menu bar...
     

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  4. r.j.s Moderator emeritus

    r.j.s

    Joined:
    Mar 7, 2007
    Location:
    Texas
    #4
    Mine is gone from the menu bar, but I can choose from three options that do the same from Optimization.
     

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  5. mayuka thread starter macrumors 6502a

    mayuka

    Joined:
    Feb 15, 2009
    #5
    Where can you choose from those options?

    I found out that this is a problem of the latest 10.5.6 Update... See attachment... (Snapshot taken from flickr)
     

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  6. mayuka thread starter macrumors 6502a

    mayuka

    Joined:
    Feb 15, 2009
    #6
    Ooops... Is it possible that the new 2009 models lack this option completely? It seems that Apple has removed that option completely for the new 2009 models? :confused::confused::confused::mad::mad::mad:

    http://support.apple.com/kb/TS2499
     
  7. mayuka thread starter macrumors 6502a

    mayuka

    Joined:
    Feb 15, 2009
    #7
    new (left side) vs. old (right side)

    what happened? :eek::eek:
     

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  8. aluminumapple macrumors regular

    Joined:
    Jan 7, 2009
    #8
    what exactly does Better performance do..? im actually curious now. i also thought about overclocking the nvidia video card, but this isnt bad either.
     
  9. mayuka thread starter macrumors 6502a

    mayuka

    Joined:
    Feb 15, 2009
    #9
    That's not about overclocking. On my old iBook it simply was another meaning for "scaling the processor speed from ~800 MHz (low performance) up to 1,33 GHz (high performance)". Maybe Apple thinks that since the intel processors have scaling built in a triggering of speed isn't necessary anymore? They still have upper and lower limits. But why can't I set them to preserve a) battery power and b) to limit the noise of the fan.

    Hasn't somebody an idea?
     
  10. harry454 macrumors 6502

    Joined:
    Sep 13, 2007
    #10
    I wouldn't personally overclock the cpu, puts more load on it, higher temps, plus then you lose a little bit of life as the cpu has to work harder
     
  11. mayuka thread starter macrumors 6502a

    mayuka

    Joined:
    Feb 15, 2009
    #11
    The thread is not about overclocking, it's about underclocking. :eek::eek: Or must I dig in OpenFirmware / EFI for that now?
     
  12. Cali3350 macrumors regular

    Joined:
    Feb 16, 2009
    #12
    The Intel processors Apple uses today have MUCH more sophisticated Energy Savings built into them then the old PowerPC cores. Your laptop is throttling its speed on-the-fly, giving you exactly however much you need in any situation. Your laptop is working smarter then your old one, that is the only difference.

    The technology is called Speedstep, you can read about it here:
    http://en.wikipedia.org/wiki/Speedstep

    If you feel you absolutely must control your own processors performance there is a open source utility that allows it.
    http://mac.softpedia.com/get/System-Utilities/xnu-speedstep.shtml
     
  13. mayuka thread starter macrumors 6502a

    mayuka

    Joined:
    Feb 15, 2009
    #13
    Many thanks for the link! That's not exactly what I'm looking for, but it's very close. :):)

    I tried it out on my intel Mac mini and I managed to set the upper limit to 1 GHz.

    # install the kernel extension:
    cp -R IntelEnhancedSpeedStep.kext /System/Library/Extensions
    chown -R root:wheel /System/Library/Extensions/IntelEnhancedSpeedStep.kext
    chmod -R 755 /System/Library/Extensions/IntelEnhancedSpeedStep.kext
    kextload /System/Library/Extensions/IntelEnhancedSpeedStep.kext

    # list possible values:
    sysctl -a | grep throttle

    # set current frequency
    sysctl -w kern.cputhrottle_curfreq=1000

    # turn off auto throttling
    sysctl -w kern.cputhrottle_auto=0

    # set upper limit to a target load of 0.90 (not needed if auto throttling is been turned off before)
    sysctl -w kern.cputhrottle_targetload=90

    I need to put these lines somehow in /etc/sysctl.conf or something similar. But there's no sysctl.conf on my system? :confused::confused:

    Since I sent back my MacBook for repair I'll test the kernel extension next week when (hopefully) my new MacBook without any problems arrives. Maybe I can safe some battery with it. That would make me very happy.
     
  14. mayuka thread starter macrumors 6502a

    mayuka

    Joined:
    Feb 15, 2009
    #14
    Oh.... What I forgot.... The cpu of my Mac mini still runs at 53°C and ~1600 rpm... It seems that it won't get any cooler as it was before... Any chance to lower the temperature of the cpu with other tools?
     
  15. r.j.s Moderator emeritus

    r.j.s

    Joined:
    Mar 7, 2007
    Location:
    Texas
    #15
    Those are perfectly normal. I wouldn't worry about it.
     
  16. mayuka thread starter macrumors 6502a

    mayuka

    Joined:
    Feb 15, 2009
    #16
    A friend of mine has exactly the same processor type in a lenovo notebook and he claims that his cpu runs with ~35°C... But maybe it's all a matter of which sensor is being used for monitoring? The harddrive has two temperature sensors where the outer sensor produces (obviously) lower values than the one inside....
     
  17. r.j.s Moderator emeritus

    r.j.s

    Joined:
    Mar 7, 2007
    Location:
    Texas
    #17
    His is probably almost always running at a low speed.
     
  18. Cali3350 macrumors regular

    Joined:
    Feb 16, 2009
    #18
    Different chasis with different cooling systems. The mac mini is a small computer with relatively poor cooling, so it runs hotter. Those temps are still very well within normal range however, so there is no need to worry.
     
  19. mayuka thread starter macrumors 6502a

    mayuka

    Joined:
    Feb 15, 2009
    #19
    what are normal ranges nowadays?
     
  20. Cali3350 macrumors regular

    Joined:
    Feb 16, 2009
    #20
    Anything below 60C is fine for 24/7 everyday use. To be perfectly honest, anything below 75C is perfectly fine, but people like to keep it cooler just to keep their conscious clean.
     
  21. mayuka thread starter macrumors 6502a

    mayuka

    Joined:
    Feb 15, 2009
    #21
    Ok. Thanks. I had those IBM "Deathstar" harddisks in use for over 8 years and they got quite hot (>80°C in summer) and survived without a problem. But that were different times back then...
     
  22. r.j.s Moderator emeritus

    r.j.s

    Joined:
    Mar 7, 2007
    Location:
    Texas
    #22
    Constant temps around 80-90C should make you worry.
     

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