DDR3 RAM in NEW Macbooks, Macbook Pros

Discussion in 'MacBook' started by lwongveros, Oct 16, 2008.

  1. lwongveros macrumors newbie

    Jun 15, 2007
    Hi everyone, I did a quick search on the forums and haven't seen anything regarding a doubt that I have....

    We all know that the new Nvidia chipset being used in the new Macbooks and Macbook Pros utilise DDR3... and specifically at 1066MHz. I downloaded the manuals for both models and they specifically call for using DDR3 at that speed.

    So.... if the chipset supports DDR3 @ 1333MHz, the questions that arise for me are:

    1. technically, will DDR3 @ 1333 MHz work in the new machines?
    2. if so, would there be any real-world performance increase?
    3. if it works, why has there been no mention of it? If it doesn't work, why?

    Hopefully someone has some insight into this... cheers!
  2. abijnk macrumors 68040


    Oct 15, 2007
    Los Angeles, CA
    Not really sure what you are getting at here. Have you read the specs for the new macbooks? They come with 2GB (two 1GB SO-DIMMs) of 1066MHz DDR3 SDRAM.

    Apple's Spec Page
  3. mgpg89 macrumors 6502a


    Aug 31, 2008
    I'm guessing he'd like to buy some 1333MHz DDR3 RAM if this is supported in the new MacBook (Pro)'s and if there's a notable speed boost.

    I'd like to know so too, actually ...
  4. Sun Baked macrumors G5

    Sun Baked

    May 19, 2002
    Generally in the Macs, all the faster memory has done in the past is boost the chance that marginal cheap memory will work.

    Putting faster memory just gets downclocked to the required speed.

    The chipset might support 1333, but it currently is running at 1066.


    If you want to hack EFI, and boost the memory speed, go ahead.
  5. lwongveros thread starter macrumors newbie

    Jun 15, 2007
    Sun Baked - thanks, I think I see how it works now... even though the chipset supports up to 1333MHz memory bus speed, in the Macbook it has been set to 1066 so installing DDR3 1333 (which I assume simply means its rated to run safely up to that clock speed) would be pointless and most likely a waste of money.

  6. TPetersen macrumors newbie

    Aug 2, 2008
    No they dont work, because there doesn't exists any 1333 MHz SO-DIMM 204 pin DDR 3 RAM.
    1066 MHz is the fastest you get, you are looking at wrong RAMs, they will NOT fit your MacBook Pro.

    You need to look after SO-DIMM 204 pin DDR3 RAM
  7. mlemonds macrumors 6502a


    Apr 9, 2008
    Lexington, KY

    isnt that 1333MHz 204 pin?
  8. sporadicMotion macrumors 65816


    Oct 18, 2008
    Your girlfriends place
  9. andalusia macrumors 68030


    Apr 10, 2009
    Manchester, UK
  10. TPetersen macrumors newbie

    Aug 2, 2008
    Okay, i didnt know that, but they are not very good, the RAM timings on this ram is CL 9-9-9-24
    Where the Kingston HyperX RAM is CL 5, and most of them are CL 7.
  11. mlemonds macrumors 6502a


    Apr 9, 2008
    Lexington, KY
    from what i could read on kingston's website, their hyperx for 1375mhz ram is 7-7-7-20. so the 9-9-9-24 that ocz is offering seems on par for the price difference. i guess that is why you pay soo much more for the hyperx ram. (also the hyperx uses a higher voltage)

    The higher your bus speed the higher the latency times are going to be, but will still give you an overall faster experience.
  12. bozz2006 macrumors 68030


    Aug 24, 2007
    I don't know much about this, so i'll throw it out there and let someone who actually knows about this stuff chime in; but doesn't the RAM kind of do double-time, so that as long as your RAM runs at half the clock speed of your FSB, faster RAM won't do anything for you????
  13. Toofan macrumors member

    May 12, 2009
    1) It depends, I wouldn't risk stability issues for the negligible 300 mhz
    2) The word negligible in answer 1 should answer question 2
    3) Try it out if you want, the fraction of time you'll be saving with increased RAM speed is laughably small
  14. blackhand1001 macrumors 68030


    Jan 6, 2009
    The cpu also only has a 1066 Front Side Bus, so i don't believe it will even run the memory at those speeds, and the even if it could, the front side bus is the bottleneck, not the ram itself.
  15. michael.lauden macrumors 68020


    Dec 25, 2008
    just put in the right RAM. seriously if there was an increase... it'd be like .002 % better
  16. pellets007 macrumors 6502a


    Jan 28, 2009
    New York
    There wouldn't be any difference, it would be a pointless task.
  17. keson macrumors newbie

    Sep 29, 2010
    Early 2010 MBP 13" 1333 MHz RAM experience

    Although late 2009 MBP 13" was running fine with Transcend 1333 MHz memory (2x4GB) when placed into early 2010 MBP 13" the same RAM does not work. MBP boots but freezes when starting loading kexts. No pram, nvram nor smc reset helped... It just can not run on 1333 :( Too bad.
  18. blackburn macrumors 6502a


    Feb 16, 2010
    Where Judas lost it's boots.
    On my macbook6,1 using 1333MHz DDR3 ram makes it run hotter and makes battery last less but it works. If you mod the spd you can get it at 1066MHz
  19. akhbhaat macrumors regular

    Sep 30, 2010
    With C2D-compatible chipsets, the memory clock is directly tied to the front side bus speed, which is in turn set against the CPU core multiplier to generate the CPU clock speed. You will see absolutely no benefit to pairing 1333 Mhz DDR3 with a CPU rated for 1066, provided said CPU is running at stock speeds. The bus (and the memory) will be set to run at 1066.

    It's common practice for desktop system builders to buy uprated memory for systems that they intend to overclock, because manipulating the FSB speed is the most common way to manipulate the clock speed of a ratio-locked CPU (at least until the advent of the Core iX architecture, which is a bit different) and this will prevent the memory itself from being a stability concern, but I would think (and hope) that you wouldn't be so daft as to attempt overclocking in a laptop. The more notable consequences (additional heat and power consumption) are not acceptable for a mobile device. It also appears to require some significant hacking to pull off with a Mac anyhow.
  20. mulo macrumors 68020


    Aug 22, 2010
    Behind you
    they will work, but will be downclocked to 1066
  21. blackburn macrumors 6502a


    Feb 16, 2010
    Where Judas lost it's boots.
    They wont be downclocked I tried that. They will work faster but you will have higher latency (CL9 instead of CL7).
    And the RAM:FSB Ratio will no longer be 2:1
  22. Phil Brinkle macrumors newbie

    Apr 12, 2011
    I would like to share a good solution how to force MacBook to work with DDR3-1333 memory modules. The problem is that the MacBook is not capable of supporting DDR3-1333 officially. But we can adjust the clock speed of the module through its SPD settings. Just download Thaiphoon Burner software, read SPD and then increase the SDRAM clock cycle time to 1,875 ns (15 MTB units) through the Timing Table Editor. And that's all! Now we've got a DDR3-1066 module which is full compatible with any MacBook.

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