Macbook Pro 2012 CPU Vcore Present No Post

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  • platinumsteel
    Badcaps Veteran
    • May 2019
    • 234
    • Trinidad&Tobago

    #1

    Macbook Pro 2012 CPU Vcore Present No Post

    Hi guys hoping you can help me solve this issue. I have 3x 820-3115 boards. One fully working with CPU Vcore 0.8v and posting which am using to compare against the other 2...The other 2 has CPU Vcore stuck at 1.12v and doesn't drop down to 0.8v.
    PPBUS_G3H is 8.56v and all other rails present. They both do not post or give picture and no caps lock. Hoping anyone may have experience with this and advise me on a few things to try. So far the only thing i tried was a few different bios for this board and nothing changed same behavior persists I have the original backups saved.Thx
  • platinumsteel
    Badcaps Veteran
    • May 2019
    • 234
    • Trinidad&Tobago

    #2
    Okay so thought I’d post how the issue was kinda solved think it might help someone.i read on the forum where someone had a similar issue and piernov mentioned that it can be a ram issue with these model boards..So I decided to try the other ram slot and low and behold the vcore dropped too 0.8v and it posted with picture. Both boards are posting now with the ram in the second slot .I tried cleaning out the first slot but that slot refuses to work on both boards.So will leave it at that for now.Just glad both boards are working. Thanks again piernov and the entire Badcaps community.

    Comment

    • mon2
      Badcaps Legend
      • Dec 2019
      • 13832
      • Canada

      #3
      https://www.youtube.com/watch?v=58dFwz4AttM

      Comment

      • platinumsteel
        Badcaps Veteran
        • May 2019
        • 234
        • Trinidad&Tobago

        #4
        Thanks a lot for the video. I inspected all my pins as in the video and all of mine are good and has a solid connection. My issue may be a little different. Only on closer inspection under the scope inside the top memory slot. I notice 1 pin is damaged. On both boards in the top slot 1 pin is kinda damaged. Really difficult to repair. Got nothing to lose will try to fix it and maybe see how that goes. But i'm just glad to at least know what the problem is with both boards.

        Comment

        • mon2
          Badcaps Legend
          • Dec 2019
          • 13832
          • Canada

          #5
          https://www.youtube.com/watch?v=1Zf_ADyjS9k

          Comment

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