Mac Pro memory board fry

Discussion in 'Mac Pro' started by sultanmakende, Jun 24, 2014.

  1. sultanmakende macrumors newbie

    sultanmakende

    Joined:
    Jun 13, 2012
    Location:
    Salvador, Bahia, Brazil
    #1
    Hi,
    This is a question for a hardware specialist:

    I have an early mac pro:
    Processor: 2.66GHz Xeon (Dual-core 5150)
    *Upgraded to 2 X Quad Core 3.2Ghz (March - 2014)
    Serial #: #CK340GSUPZ
    Model #: A1186
    Year : Aug 7, 2006 - Jan 8, 2008
    OSX 10.7.5

    Recently I tried to upgrade the memory from some older combinations of 1 and 2 GB DDR2 FBDIMMs - 667 MHz memory modules

    to:

    4 x 4GB DDR2 800MHz PC2-6400 FBDIMMs to make a total of 16GB. (I don't think the makes should be relevant, but can supply if needed).

    They came in matched pairs of 4GB each and I placed them as recommended with the first pair in slots 1 & 2 in the top riser A, and the 2nd pair in slots 1 and 2 in riser B.

    When I tried to boot, the power switch started to flash and it would not boot, which (I think) signifies a memory problem.
    So I tried placing all the DIMMS on the same top memory riser A, even though this is not the recommended configuration - same result.

    I then tried just placing a single DIMM of the new 4GB in slot one of the top riser A and it booted ok.

    I then went back and tried all kinds of combinations, including mixing some of the older 1 and 2 GB DIMMS with the new 4 GB DIMMS, but always in matched pairs, top and bottom.
    I also tried putting the old memory back in as I first found it - before any boot problem.

    But now. NON of the memory works at all in any combination and the risers have the red problem alert LEDs all lit up.
    So I'm thinking that either I might have fried all the DIMMS or even worse, damaged the memory riser boards, or both.
    (And I'm really hoping that I didn't also damage the logic board in any way).
    I live in Salvador, Brazil where there is no reliable Apple tech service, so I have to try and resolve any issues myself.
    Any help, tips, info would be a great help as I am a musician / composer and I make my main living via my Mac Pro.:confused:
     
  2. LiamHD macrumors member

    Joined:
    Jun 5, 2014
    #2
    are you sure both riser cards are correctly seated in the slot in the logic board?
     
  3. omvs macrumors 6502

    Joined:
    May 15, 2011
    #3
    Besides reseating the riser cards, you might want to try swapping them and see if that helps.

    I feel your pain though - was trying to help an inlaw do a upgrade on that machine but long distance - we ran into all sorts of problems, and a few times she didn't get the memory seated right.

    Not following the order in the manual usually resulted in memory not being recognized - she didn't always follow the diagram and put the pairs in the wrong spot. The most common mistake was when going from 1 pair to 2 pairs you have to take the 2 dimms that were split and move both to the top., then populate the bottom with matched pairs.
     
  4. sultanmakende thread starter macrumors newbie

    sultanmakende

    Joined:
    Jun 13, 2012
    Location:
    Salvador, Bahia, Brazil
    #4
    Depends what you mean by "correctly seated".
    I cleaned them both with contact cleaner as well as the slots.
    The 4 problem memory LEDs light up now all the time even with the old memory back in their original positions.
    New questions:
    1. When I press the SMC reset button, two red CPU LEDs briefly flash. Does this mean that the CPUs are dead?
    2. If there is a problem with the CPUs, would the memory riser red LEDs still light, even if there is no problem with the memory and the risers?

    ----------

    Sure, I tried the standard Apple recommended way first, then every possible combination.
    New questions:
    1. When I press the SMC reset button, two red CPU LEDs briefly flash. Does this mean that the CPUs are dead?
    2. If there is a problem with the CPUs, would the memory riser red LEDs still light, even if there is no problem with the memory and the risers?
     
  5. Umbongo macrumors 601

    Umbongo

    Joined:
    Sep 14, 2006
    Location:
    England
    #5
    3.2GHz quad cores aren't supported, do you mean 3GHz?

    Also 800MHz FB-DIMMS aren't supported. I would have expected them to just downclock to 667MHz rather than all you experienced, but you have used parts that weren't intended for the Mac Pro.
     
  6. sultanmakende thread starter macrumors newbie

    sultanmakende

    Joined:
    Jun 13, 2012
    Location:
    Salvador, Bahia, Brazil
    #6
    Hi Umbongo, thanks for that info. Strange that the suppliers of the memory say that it is compatible.


    http://www.amazon.com/dp/B0085MGUBS/ref=pe_385040_30332200_TE_item

    Without taking off the cooling towers, I can't confirm the exact speed of the processors, but looking through my ebay purchases I found this, so maybe they are in fact 3.Ghz CPUs:

    Apple 661-3919-3G Mac Pro 3GHz Logic Board w/CPUs 820-1976-A 630-7608 A1186

    Also, with just one of the modules in place in slot 1 / Riser A, it did boot up ok, but now not any more, even with the older original memory back in it's original positions.

    So can you confirm that the memory was totally wrong and perhaps I should just look for some more 667Mhz memory?
    And maybe I should go for Kingston as macs seem to be happiest with them?
    My fear is that I might have also burned something either on the memory risers and / or logic board and buying yet even more expensive memory, won't solve my problem.
     
  7. G4DP macrumors 65816

    Joined:
    Mar 28, 2007
    #7
    The memory you purchased is for the 2008 models. Although as Umbongo pointed out it should just run at 667mhz.

    If you are still not having any luck, try finding some of the 2006 model ram from crucial.

    http://www.crucial.com/usa/en/compatible-upgrade-for/Apple/mac-pro-(8-core)-1st-gen*---2006-2007
     
  8. LiamHD macrumors member

    Joined:
    Jun 5, 2014
    #8
    Make sure when you push the ram riser cards back in that they "CLICK"
     

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