Lenovo B50-45 dead after APU change

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  • homeless_cz
    Member
    • Oct 2017
    • 18
    • Czech rep.
    #1

    Lenovo B50-45 dead after APU change

    Hi, I'm a bit despered of this laptop.
    The board is Compal LA-B291P which worked but AMD APU was defective causing random sudden reboots.
    So I decided to replace APU E1-6010 with better one compatible.
    First I updated bios to latest, all OK. Then I desoldered old APU and put new one A8-6410 - the same platform "Beema" . Since that time no init, black screen.
    All voltages OK, checked power sequence, all signals between EC and APU are OK, susp# signals goes high, SPI has read activity, the only thing I miss is Backlight ON and a picture.
    Today I decided to replace APU for new one A6-6310 and it is still the same.
    Tried 2 bios dumps, still the same.
    I will appreciate any suggestions. Scheme attached.
    Attached Files
    Tags: None
    • mcplslg123
      Badcaps Legend
      • Jun 2015
      • 7262
      • india
      #2
      Re: Lenovo B50-45 dead after APU change

      Pcb tracks not damaged??

        Comment

        • homeless_cz
          Member
          • Oct 2017
          • 18
          • Czech rep.
          #3
          Re: Lenovo B50-45 dead after APU change

          Nothing visible under magnifier.
          I can't believe that 2 of 2 new APUs could be bad the same way...

            Comment

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