Can upgrading RAM reduce battery life?

Discussion in 'MacBook Pro' started by karohan, Feb 3, 2011.

  1. karohan macrumors 6502

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    Jun 25, 2010
    #1
    I just installed a new set of 8gb RAM. Is it possible that upgrading RAM can result in lowered battery life (even a minor decrease)? The clock speeds and all the specifications besides the size of the RAM are the same.
     
  2. Tomorrow macrumors 604

    Tomorrow

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    #2
    Naahhhh, don't worry about it.

    CPU-intensive applications, maybe. RAM? No.
     
  3. goMac macrumors 603

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    Apr 15, 2004
    #3
    It would be imperceptible, but in theory yes.
     
  4. SandboxGeneral Moderator

    SandboxGeneral

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    #4
    Actually in a worst case scenario, more RAM may save battery life. If RAM is so little and the computer has to use the swap file a lot, it would require more CPU processes and hard drive activity which translates to more battery consumption. By adding RAM, it will eliminate all that extra work and save some battery power.
     
  5. NickZac macrumors 68000

    NickZac

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    Dec 11, 2010
    #5
    It is possible that if you had an uneven balance, say 6GB and 2GB sticks, it may reduce battery life some, but even that would be minimal. Reduction from 4 - 8 is minimal at best.
     
  6. Hellhammer Moderator

    Hellhammer

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    #6
    6GB RAM modules don't exist.
     
  7. goMac macrumors 603

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    #7
    This is true, it might save hard drive spinups, which take far more power.

    The reason extra RAM takes extra power is that RAM continuously has to refresh it's contents or else they will be lost, and this takes power to do. The more RAM you have, the more content to refresh, and the more power required.

    Although it's really an inperceivable amount of power required to do the refresh.
     
  8. GGJstudios macrumors Westmere

    GGJstudios

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    May 16, 2008
    #8
    You're unlikely to see any difference in battery life due to increased RAM, unless you had been suffering from extensive paging before the increase. In that case, you may see a slight improvement from reduced paging. Also, you may notice a slight decrease in battery life in sleep mode, as slightly more power is required to power the additional RAM. Again, the difference will likely be imperceptible.

    Other factors have a much larger impact on battery life, such as screen brightness, WiFi, bluetooth, apps/processes/widgets running, etc. This should answer most, if not all, of your battery questions: Apple Notebook Battery FAQ
     
  9. ExiledMafia macrumors regular

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    Jan 26, 2011
    #9
    It may a little but probably nothing substantial.....if your trying to get a speed upgrade may I suggest using a SSD?
     
  10. karohan thread starter macrumors 6502

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    Jun 25, 2010
    #10
    Okay sweet, I felt like I was being paranoid. It's probably just the fact that I have like 40 tabs open that I'm noticing a little less battery life =D
     
  11. GGJstudios macrumors Westmere

    GGJstudios

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    May 16, 2008
    #11
    I frequently have 20+ tabs open. As long as there isn't a lot of Flash, it shouldn't affect battery life too much. I use ClickToFlash plugin to restrict Flash on sites.
     
  12. karohan thread starter macrumors 6502

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    #12
    Yeah I really liked ClickToFlash, but unfortunately it doesn't work with Chrome, which I prefer to Safari.
     
  13. Hellhammer Moderator

    Hellhammer

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    #13
    Use FlashBlock
     
  14. fibrizo macrumors 6502

    fibrizo

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    #14
    I would say yes in theory, no in reality, ie there are more ram chips to power, and all voltages being equal, you'd see more drain just powering the ram, but realistically you'd probably be looking at... say 5 hours and 59 mins vs 6 hours
     
  15. NickZac macrumors 68000

    NickZac

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    #16
    Theoretical illustration ;)

    I had a 4GB and a 2GB RAM stick in the MBP and was playing with it. Battery life was slightly lesser than 4+4 or 2+2, but this difference was small. Performance wise it was not really affected by the 2 different sizes operating together.
     
  16. runofthedill macrumors member

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    Dec 22, 2010
    #17
    since I put 8 gigs in it seems like my battery isn't nearly as high. But let me also say that I usually have 15 programs open at a time now.
     
  17. jakedaugherty macrumors newbie

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    Feb 12, 2012
    #18
    I have a mid 2010 13" Macbook Pro. I was getting about 7 hours just browsing the web with 4 gb (2X2gb) RAM. I upgraded last week to 8 gb (4X4gb) and immediately went to a max time of 5 hours doing the exact same activity as before.
     
  18. Starfox macrumors regular

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    Apr 7, 2011
    #19
    My battery life also dropped as I went from 4 to 8 GB and from 8 to 16 GB.
     
  19. dusk007 macrumors 68040

    dusk007

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    Dec 5, 2009
    #20
    That is because it does.
    Twice the ram usually needs close to twice the refresh power. That is some 200-300 mW. Under load it is about 2W extra for doubling RAM.
    It is nothing huge but is something. 16GB is more still.
    With an idle mit power draw of 7W a MBP that can be 5% less idle battery life.
    Going from 4 to 8GB is comparable to the power a hdd draws. Almost like adding a second HDD in a way.
     

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