problems arise when Bank 1 has memory

Discussion in 'MacBook Pro' started by stonewall777, Jan 14, 2014.

  1. stonewall777 macrumors newbie

    Feb 18, 2010
    mid 2009 MBP 15"

    I've discovered that when ever memory is installed
    in bank 1, the computer will beep when boot up,
    either a single beep or 3 beeps, indicating memory issues.

    But when this bank is left empty, the machine seems to
    be very stable, no freezes or boot problems.

    Anyone have any experience fixing this, short of logic
    board swap.

  2. Swampus macrumors 6502


    Jun 20, 2013
    You didn't explicitly say so, but I'm assuming that you swapped the RAM around in order to narrow in on the slot rather than a bad memory module?

    If so, problem could be with slot itself or elsewhere on the board. In either case, Apple's approach would be to replace the entire logic board.

    Maybe check around your city for a shop that does board level diagnostics and repair? You'd probably be looking at a few hundred dollars doing it that way.

    Honestly, I'd just stick a 4GB module in the good slot and call it a day.
  3. bobcan, Jan 16, 2014
    Last edited: Jan 17, 2014

    bobcan macrumors 6502a


    Jan 8, 2007
    Sunny but Cold.. Canada
    As noted above, to 'complete the trouble-shooting analysis' you would have to confirm whether you DID Swap 'Slot 0 and Slot 1' RAM, with same '3 Beeps' being the result.. ** That tone burst is the indication of RAM/ Slot Error..:(

    I know this only because my 2011 MBP had this exact issue ~ No matter what RAM stick I would insert into Slot 1, it would 'error', but could limp along on Slot 2 just fine!! I did for a week until my local Apple Repair Depot got parts in (pretty sure it was a Logic Board Replace, Applecare was my friend) and got it back a day later, has been great since.. I recall that the piece was 'listed' as ~$900 item though.. OUCH indeed!! :eek:
  4. stonewall777 thread starter macrumors newbie

    Feb 18, 2010

    I did swap everything around as you mentioned.

    It turns out I had 2 4MB modules from different
    manufacturers. And I didn't notice that.

    I just grabbed these from a machine that had 4 4MB
    modules, and in that machine it didn't seem to matter,
    I think each brand was in the same row. iMac 2010 27"

    Anyway, I guess you have to use bank 0 before having
    anything in bank 1.

    No matter, I now have 2 4MB modules in bank 0 and 1,
    and it seems to be working OK as far as memory issues

    The USB's are tits up, but that's another issue.
  5. thundersteele macrumors 68030

    Oct 19, 2011
    So you bought new RAM and it is working again?

    I'm asking because I have the same problem, after some trial and error I figured out that having RAM in the lower bank will lead to three beeps eventually, while the top bank seems to be working fine. Now I'm not sure whether to try and go for new 2x4 GB or whether I should just buy 1x8 GB to get back go my 8 GB config.
  6. stonewall777 thread starter macrumors newbie

    Feb 18, 2010
    It started acting up again.

    I did have a 4MB in each memory slot.

    If you check the system report, memory area,
    you can see what's in bank 0 and bank 1.

    Now, once again after getting system freezes,
    I have removed the memory from bank 1,
    and it seems to be fine.

    It's still running.

    This is an ebay parts machine that I'm tinkering with.
    But these are very nice machines.

    It seems there is something with the bank 1 memory.

    I also noticed that the power section showed that it
    was set to power on everyday at 9 am. I didn't set this,
    and it doesn't make any sense that this would be a default
    setting. It makes me wonder if there is a way to return a
    logic board to factory settings, to clear absolutely everything
    that might cause a problem.

    I think I'll just use memory slot 0 with 4MB and press on with it.
  7. Gav Mack macrumors 68020

    Gav Mack

    Jun 15, 2008
    Sagittarius A*
    If could be dust related.

    Disconnect battery, blow slot 1 out with compressed air, and with a fine blade spudger wrapped in a lint free cloth with a few drops of denatured isopropyl both sides clean the contacts out and blow with air again. Let dry for 30 mins - 1 hour then power it up see if slot 1 works. If not it's logic board unless you can re-ball SO-DIMM slots!

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