La-7912p second board

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  • ziko07
    Senior Member
    • Jun 2021
    • 93
    • Somewhere
    #1

    La-7912p second board

    Hi

    I openet new topic becouse now diferent problem to this board
    Board power On , and without Ram module has CPU_CORE 1.2V on both phases
    But when insert Ram memory in slot then board has power On with cpu_core and restart and once again core is 1.20v and then drop and no more cpu_core present.
    At this point I can see also on RAM that DIMM_DRAMRST# is missing (but think this should not affect cpu_core missing)
    All voltage is OK on RAM except [pin-30]

    Like something other couse problem,but this happend only when insert memory

    Any help?
    Attached Files
    Tags: None
    • mcplslg123
      Badcaps Legend
      • Jun 2015
      • 7262
      • india
      #2
      Re: La-7912p second board

      The mb tries to go higher up in sequence(S0 rails) with ram inserted but when ram is not inserted this sequence is interrupted-so it wont reboot and stay on.

      Problem is very likely related to SIO.

        Comment

        • ziko07
          Senior Member
          • Jun 2021
          • 93
          • Somewhere
          #3
          Re: La-7912p second board

          Hi, board power on ok but after 30-50 seconds all 3 usb stop working. On external keyboard led goes off and I see when I put freeze spray at pch keyboard leds works ok but shortly and goes off again
          Is it pch damaged?
          When put external power without battery and lcd it takes 28mA,isn't that much?
          Last edited by ziko07; 10-04-2023, 12:19 PM.

            Comment

            • mcplslg123
              Badcaps Legend
              • Jun 2015
              • 7262
              • india
              #4
              Re: La-7912p second board

              28mA seems a bit higher but not alrming as this platform has 3V/5V ALW on coil as soon as you insert adapter in dc jack.Perhaps should be 15-20mA but not sure as dont remember the exact offline consumption on this board and these boards hardly comes for repair these days.

                Comment

                • ziko07
                  Senior Member
                  • Jun 2021
                  • 93
                  • Somewhere
                  #5
                  Re: La-7912p second board

                  PCH has no cooler but getting quickly pretty hot

                    Comment

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