Resolved Strange RAM phenomenon

Discussion in 'MacBook Pro' started by poiihy, Nov 28, 2014.

  1. poiihy, Nov 28, 2014
    Last edited: Nov 29, 2014

    poiihy macrumors 68020

    poiihy

    Joined:
    Aug 22, 2014
    #1
    Today the RAM I bought from ebay arrived. After installing it into my MBP, I discovered it did not work. Tried different arrangements with no luck, and it did not work in the iMac either. Soon after I started writing a thread about it, I discovered my mistake. On Apple's support page about MacBook Pro RAM, clicking Mid-2009 MacBook Pro scrolled me down to the beginning of the section instead of directly to the table for 2009 MBP. So I was reading the table for the 2012 Mac instead of 2009 Mac and this is why I got the wrong RAM. Luckily it had a hassle-free return policy, so I am returning it.

    The RAM i bought from ebay was 1600MHz RAM. My MacBook Pro takes 1066MHz RAM. Probably why it didn't work. But this confused me, because the original RAM that came with my MBP (it was bought from eBay) was 1333MHz RAM (2x4GB) and it worked. It worked, but it crashed randomly. I thought that RAM was defective. But perhaps this RAM is not defective after all... perhaps it was just causing my computer to crash randomly because it was the wrong speed. Could it be? If so then I could sell it and use the profits to pay for replacement RAM!

    TL;DR Could higher RAM speeds than required for a Mac cause erratic behavior? Could the 1333MHz RAM which I thought was defective be actually not?
     
  2. poiihy thread starter macrumors 68020

    poiihy

    Joined:
    Aug 22, 2014
    #2
    Also here are some pics of the RAM sticks I was going to use for the thread I was going to make but canceled.
     

    Attached Files:

  3. rigormortis macrumors 68000

    rigormortis

    Joined:
    Jun 11, 2009
    #3
    did you actually try running apple hardware test in extended mode to test any of the memory ?
    im not a ram expert, but i thought as long as the notch is in the right place it should of worked


    you either
    insert the disks that came with the computer and hold the D key
    hold down d during boot
    hold down command d during boot
    hold down option command d during boot

    maybe the random crashing is something else. like i dunno. your heatsink is bad

    A.H.T might error if you don't have the power cord plugged in. so keep it plugged in
     
  4. poiihy thread starter macrumors 68020

    poiihy

    Joined:
    Aug 22, 2014
    #4
    I already solved the crashing problem and found it to be bad RAM. I used Memtest86. It was that 1333MHz ram. I am just wondering if it is really actually bad or if it is just glitchy because it is not the right one for my system. It also causes my iMac to crash; the iMac is similar to the MacBook Pro, they both use 1066MHz RAM. I have no system that takes 1333MHz RAM; all i have is the MacBook Pro and iMac. I have an rMBP but that has soldered RAM.

    If it is indeed fine and just an incompatibility glitch, then I can resell it and use the profits for replacement RAM.
     
  5. rigormortis, Nov 28, 2014
    Last edited: Nov 28, 2014

    rigormortis macrumors 68000

    rigormortis

    Joined:
    Jun 11, 2009
    #5
    we put in PC3-12800 into a mac book pro 2011 which requires PC3-10600 DDR3 and it was fine. i bought it simply because it was only $71 and cheaper then the other ram chips which were on the mac book pro 2011 list

    its my opinion but first you run AHT and then you run memtest86

    update
    i checked my amazon order history. the 1066MHz DDR3 SODIMM ram chips i bought for my mac mini 2010 C2D are worth $173 now, because no one manufacturers slower memory anymore
     
  6. poiihy thread starter macrumors 68020

    poiihy

    Joined:
    Aug 22, 2014
    #6
    I've heard that you can put RAM speeds one notch higher than the specified one, but any more than 1 notch and it may/will not work. For example, if device specifies 1066MHz RAM, 1333MHz RAM will work but 1600 will not. If device specifies 1333MHz, 1600MHz RAM will work but the next one will not.

    Seems like this 1333MHz ram I have is indeed defective.
     
  7. rigormortis macrumors 68000

    rigormortis

    Joined:
    Jun 11, 2009
    #7
    i checked my windows 7 machine. it has 15 gigs of triple channel memory
    and half the ram chips are pc3-8500 and the other half are pc3-10700 heh
     
  8. poiihy thread starter macrumors 68020

    poiihy

    Joined:
    Aug 22, 2014
    #8
    And no crashes?

    This Patriot RAM I have must be defective then... oh well
     

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