Undervolting MBP i5/i7

Discussion in 'MacBook Pro' started by macdude66, Aug 17, 2010.

  1. macdude66 macrumors newbie

    Joined:
    Aug 17, 2010
    #1
    Hi folks,

    is there any possibility to undervolt the Core i5/i7 processor on a MBP yet? Coolbook does not support i5/i7.

    Please don't post stuff about the sense of undervolting.

    Thanks,
    macdude66
     
  2. yamabushi macrumors 65816

    yamabushi

    Joined:
    Oct 6, 2003
    #2
    Not sure what your goal is but if power savings is the goal you can do a lot by yourself. There are various system settings you can change to reduce the CPU load which will keep it pretty cool most of the time. Also you can save energy in a number of ways such as by reducing the screen brightness.
     
  3. macdude66 thread starter macrumors newbie

    Joined:
    Aug 17, 2010
    #3
    Reduced voltage -> Less heat -> Less fan noise

    Again, I don't want to discuss advantages/disadvantages of undervolting or other advices to increase battery life. Just if anyone has managed to do it on a Core i5/i7.

    Thanks.
     
  4. yamabushi macrumors 65816

    yamabushi

    Joined:
    Oct 6, 2003
    #4
    Well since the system and underlying hardware communicate there are several methods of accomplishing heat reduction. I am simply suggesting that there may be multiple methods to achieve your goal, including undervolting but also including methods such as underclocking.

    Since you never said anything about your intent in your first post or anything about about being opposed to other advice I offered some. I happen to have some knowledge about undervolting that may or may not help.

    It appears that I may have offended you in some way by trying to be helpful. If so, I apologize and won't bother you further.
     
  5. macdude66 thread starter macrumors newbie

    Joined:
    Aug 17, 2010
    #5
    Yamabushi, please excuse me if I offended you. I should have been more precise in my first post. If you have any advice how to undervolt an i5/i7 (MBP) under 10.6.x, I would be very interested in it.
     
  6. Macsavvytech macrumors 6502a

    Macsavvytech

    Joined:
    May 25, 2010
    #6
    Not sure what apart from cool book would do it but personally under volting a processor voids your warranty, can fry your motherboard and slows down your computer.
    If your wondering how you can fry your motherboard by reducing the draw under certain circumstances it can increase the current on another electrical component frying it. if you want to cool your laptop use this:
    http://www.macupdate.com/info.php/id/23049/smcfancontrol
    For battery check activity monitor for running programs, turn of bluetooth, reduce backlight on keys and screen brightness, reduce Mac osx visual effects, get and ssd, have less peripherals and more.
     
  7. miles01110 macrumors Core

    miles01110

    Joined:
    Jul 24, 2006
    Location:
    The Ivory Tower (I'm not coming down)
    #7
    I'm sure it's possible, but I haven't seen it done yet. Probably because it's unnecessary and risky.
     
  8. iPhysicist macrumors 6502a

    iPhysicist

    Joined:
    Nov 9, 2009
    Location:
    Dresden
    #8
    How can this void my warranty? Every modern Intel does it by itself... how can it fry my computer, what part exactly? It wont slow down the computer in any way if its done correctly.

    PLEASE SHARE YOUR WISDOM! ...Voltage Current Resistant Capacity Inductance... all the same? Get precise.

    And this will help undervolting? This is not even close to answering the TS question.
     
  9. macdude66 thread starter macrumors newbie

    Joined:
    Aug 17, 2010
    #9
    Warranty: No change is permanently done to the CPU. Just uninstall the program, reboot and you're good.

    Fry the mainboard: That is just wrong. I know what I'm talking about.

    Slow down computer: Do you know the difference between undervolting and underclocking?


    That is your opinion.
     
  10. Frosties macrumors 6502a

    Frosties

    Joined:
    Jun 12, 2009
    Location:
    Sweden
    #10
    For undervolting use core2due the 13" still has it, the i5/i7 has new design when it comes to speedstepping. It's that easy.
     
  11. miles01110 macrumors Core

    miles01110

    Joined:
    Jul 24, 2006
    Location:
    The Ivory Tower (I'm not coming down)
    #11
    No, the statement that undervolting causes multiple issues on unsupported hardware is not an opinion even though you seem to want it to be.
     
  12. iPhysicist macrumors 6502a

    iPhysicist

    Joined:
    Nov 9, 2009
    Location:
    Dresden
    #12
    Its very helpful to know at least little about how this whole thing works. Undervolting the CPU does only affect the CPU and nothing else. If the CPU fries because of undervolting its a crash at its best but nothing harmful to hardware.

    but a nice catchphrase by people who do not know better.

    The voltage is adjusted to guarantee a stable state of processing. Because it can vary from chip to chip Intels sets a voltage where every chip will run just fine.
    But if this stable state can be achieved by lower voltage everything still is fine.

    Thats why you can undervolt (or overclock) the latest C2D in a wide range without crashes. The production of these "outdated and ancient piece of technology" has evolved over the years to a state where (nearly) every chip could easily be sold at the fastest stepping. This is not done due to financial matters.

    My C2D is @ 0,9750 V @ 2,53 GHz (0,9625 is stable too, 0,9500 becomes unstable after a few hours of full load but its still impressive!) and no crash in sight.

    Maybe interacting with voltage is harder when it comes to integrated graphics. Maybe that is the reason no one wrote a tool to overrun Intels settings.
     
  13. macdude66 thread starter macrumors newbie

    Joined:
    Aug 17, 2010
    #13
    Miles, the Core i5/i7 perfectly support undervolting. You can look it up at the Intel specs if you want. Also, in the first post I kindly asked not to post undervolting-is-evil statements. I know exactly what I'm doing and why. The question was if anyone has done it under 10.6.x already.
     
  14. Azathoth macrumors 6502a

    Joined:
    Sep 16, 2009
    #14
    I don't know of any way of doing it, and Apple doesn't release the APIs for that. I would suggest looking at the macports stuff and see if there is any port of Intel's powertop utility.

    I'd like to be able to lock the multiplier - i.e. prevent OS X from setting the CPU to full speed when it thinks that Facebook wants to use a bit more CPU (NB - notice how much CPU two finder scrolling uses!).

    Re: the dangers of undervolting. I can't think of a mechanism by which undervolting will damage the HW (and I'm a HW designer ). It *could* cause system corruption by reducing the signalling margins and thereby increasing the likelyhood of a data errors, which may or may not be correctable.

    Im sure that Intel sets the voltage as low as possible, and depending on the process uniformity there is probably little to gain. My suggestion of locking the CPU clock to prevent jumping into high voltage/high freq. mode would be the safest way of accomplishing a power saving. My experience from this board unfortunately suggests that I won't get a meaningful answer to this... :-s
     
  15. Macsavvytech macrumors 6502a

    Macsavvytech

    Joined:
    May 25, 2010
    #15
    Sorry about the confusion my post was based on a what I thought was a reliable source reliable source which I no longer trust. I did however neglect your initial request to not make any posts about undervolting is evil now that I fully understand your question and have rethought my approach I believe atleast for now you are out of luck.
    This is a interesting idea and if you could message me if you find any outside info I would be grateful.
    Oh and good luck and may I ask does lowering the voltage increase battery? I suspect it would greatly thus being the reason for your wish to undervolting the CPU ( I also have I i5/i7)
     
  16. Consultant macrumors G5

    Consultant

    Joined:
    Jun 27, 2007
    #16
    Easiest way is to take out the battery = half speed.

    If heat is the issue than you should look into the source of the problem, which is CPU usage. Reducing CPU speed won't help you at all.
     
  17. macdude66 thread starter macrumors newbie

    Joined:
    Aug 17, 2010
    #17
    Take out battery: Great advice on a MBP with i7.

    Reducing CPU speed: Are you sure you understand what this discussion is about? Google undervolting.
     
  18. Macsavvytech macrumors 6502a

    Macsavvytech

    Joined:
    May 25, 2010
    #18
    After my first post i read up on undervolting and undervolting is not reducing cpu speed but the draw of the cpu safely lowering it can reduce temperature by 10 degrees and extended the battery 20-30minutes
     
  19. rmbrown09 macrumors 6502a

    rmbrown09

    Joined:
    Jan 25, 2010
    #19
    I'm sorry dude, I come from the hardcore let's undervolt, overclock and install custom GPU drivers PC world..... once

    I get it.

    Everyone else here seems to think
    1. You are having overheating problems
    2. you can't do it
    3. you're an idiot
    4.

    [​IMG]


    I am as well interested, I tried dabbling with it a little back when I had my prev rig (see sig for both)

    but now with this lappy I am unable to with Coolbook as well.
    I think we just have to wait for them to support it.
     
  20. bobbytomorow macrumors 6502

    bobbytomorow

    Joined:
    Nov 10, 2007
    Location:
    Left Coast
    #20
    yup AFAIK that is the only option, wait until coolbook is updated again (they update often)

    I looked into this quite extensively (for a free alternative to coolbook for myself) and came up empty. Looked through forums, private sites I am a member of(totally legit of course :D), googled to hell and back etc...no dice, only thing available to my knowledge that undervolts is coolbook and so far i5/i7 is unsupported
     
  21. Macsavvytech macrumors 6502a

    Macsavvytech

    Joined:
    May 25, 2010
    #21
  22. ph4nt0ma5ter macrumors newbie

    Joined:
    Jun 6, 2010
    #22
    MBP i7

    Hi,
    undervolting is usual between the UserInterface and the cpu be apply. If you have good analyser you can see the clock, multiplyer and voltage up and down by its own..
    Undervolt or underclock for what I know doesn't damage it but can corropt data. For long years I use downclock and uncervolt software to make a lot of computer maintain usable. fans by it self doesn't do the job and if the computer get to hot.. their material begin to deteorate day by day. Manufactures sell computer by thinking on the next one to sell, so yeah it's we the one who have to take care of what's ours.

    I'm really new to mac stuff for what I found coolbook do the job but it's incompatible with i5/i7 at least for now. I have a MBP i7 so I have to wait and search for more.
    If you're a user that doesn't need superAwsomeCPUpower then with those little babies working at batteries we get... fresh air.. and more more time more than apple anticipated for sure. if you're going to use power for some time deactivate de software and you are up.

    on more thing the SO try allways to get the best performance so every time the cpu is needed there is a max use of the cpu then so if you are using the cpu the OS gives their maximum perfomance regardless if is temporary or not. with the turbo boost of i7 ... hooooo... their maximum performance is very beyond any cooling system.

    If anyone knows any alternative to coolbook compatible with i7 I appriciate a comment/reply. thanks
     
  23. Mac32 macrumors 6502a

    Joined:
    Nov 20, 2010
    #23
    Does anyone know if there's any progress in this area? Are there any programs available that can undervolt i5/i7 CPUs? Is this something for future CoolBookController updates, or are there other programs for macs that can do this?
    Thanks. :)
     
  24. ph4nt0ma5ter macrumors newbie

    Joined:
    Jun 6, 2010
    #24
    coolbookcontroller

    unfortunetly undervolting in coolbook isn't now working(by you change it, the program itserf do it by its own) but you can switch between mhz and remove some mhz stages and limit to a certain temperature. I have to pay for it to that stage of settings.
     
  25. DWBurke811 macrumors 6502a

    Joined:
    Jun 10, 2011
    Location:
    Boca Raton, FL
    #25
    I don't really get what you mean, CoolBook still works for me(on a C2D); a few days ago I added another step in clock speed so I could drop the voltage a little more(I'm going to push it as far as I can lol, still no kernel panics). If you're trying to use it on a iX processor that's your problem, it isn't supported for i5/i7 processors [yet].


    Unfortunately, I still don't think there are any alternatives out for the iX line. I'm wondering if there's something inherent to the chip, or something that Apple has done, that won't allow it? Im assuming the chip is still able to be undervolted, so maybe someone with a lot more knowledge about these things than me could answer?
     

Share This Page