Biostar M7VKD recapping

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  • BlakeW
    Member
    • Apr 2008
    • 13
    #1

    Biostar M7VKD recapping

    Hi all,
    I identified this board as having bad caps... i've replaced the high value ones with some other similar value capacitors (note that i have no idea what brand they are, the only noticable markings are "7123MB" and "W"), however the board doesn't even get to POST. no beeps either.

    I'm wondering how i should trouble shoot this. should i check the voltages at the regulators and check for proper continuity?
    Tags: None
    • kc8adu
      Super Moderator
      • Nov 2003
      • 8832
      • U.S.A!
      #2
      Re: Biostar M7VKD recapping

      always post pics.
      look under manage attachments when you post.
      btw did this board post before the recap?

        Comment

        • BlakeW
          Member
          • Apr 2008
          • 13
          #3
          Re: Biostar M7VKD recapping

          I completely neglected to test the board before i went for the replacement, as the caps looked so awful that i didn't trust it.

          attached is the only in-focus pic of the old caps i could find.
          Attached Files

            Comment

            • zandrax
              Hit and miss
              • Dec 2007
              • 1157
              • Italy
              #4
              Re: Biostar M7VKD recapping

              Welcome Blake: those G-Luxon were obviously bulged, some even started to leak. You recapped the whole vrm and motherboard still doesn't post: it doesn't even start or it power on and switch off an instant later?
              In first case chances are regulators are damaged: there is a step by step vrm checking guide in Badcaps forum, but I can't find it. Damn ...
              In second one something prevents the boot: there are a lot of plausible reassn, such as bulging/shorted minor caps, corrupted cmos or some ICs burned.

              Zandrax
              Have an happy life.

                Comment

                • i4004
                  Badcaps Legend
                  • Oct 2006
                  • 2029
                  #5
                  Re: Biostar M7VKD recapping

                  testing
                  https://www.badcaps.net/forum/showth...ht=testing+vrm

                    Comment

                    • BlakeW
                      Member
                      • Apr 2008
                      • 13
                      #6
                      Re: Biostar M7VKD recapping

                      Ok, for some reason the computer now gets to POST, but it's saying "BIOS ROM checksum error"... and is only accepting floppy boot disks. i've tried flashing the rom with the official rom file and flash program, but still no luck. also, it doesn't like more than one ram stick in at a time... should i replace the 1000uf G-Luxons also? [/stupid question]

                        Comment

                        • BlakeW
                          Member
                          • Apr 2008
                          • 13
                          #7
                          Re: Biostar M7VKD recapping

                          ah sorry about that, turned out to be incorrect fsb and ratio settings... i'm in the bios now, will check the voltage levels.

                          got a vcore of 1.65V, +3.3V rail is at 3.20, +5V is at 5.05, and +12 is at 12.30.

                            Comment

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