Gigabyte B460M DS3H blown standby regulator, hot 5v(?) Regulator

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  • nubie
    Senior Member
    • May 2010
    • 63
    #1

    Gigabyte B460M DS3H blown standby regulator, hot 5v(?) Regulator

    Please help me ID the blown chip and point me where the short might be.

    I have a L1085DG that is getting really hot and a blown up standby regulator (I assume, one leg is ground, one leg is 5v standby, the other has 180 Ohms to ground.

    The L1085DG is in the front corner of the board. With no standby power I am using a jumper to get the PSU powered on.

    Anything I should check first for a short?

    Edit: I can look again but I don't think the USB are shorted, on back or the headers. The USB2.0 are powering up my portable monitor, so I don't think that's the problem. Does this L1085 run off the 12v rail?
    Attached Files
    Last edited by nubie; 01-05-2023, 06:11 PM.
    Tags: None
    • bbanana
      Father Land
      • Oct 2021
      • 164
      • Vietnam
      #2
      Re: Gigabyte B460M DS3H blown standby regulator, hot 5v(?) Regulator

      Originally posted by nubie
      Please help me ID the blown chip and point me where the short might be.

      I have a L1085DG that is getting really hot and a blown up standby regulator (I assume, one leg is ground, one leg is 5v standby, the other has 180 Ohms to ground.

      The L1085DG is in the front corner of the board. With no standby power I am using a jumper to get the PSU powered on.

      Anything I should check first for a short?

      Edit: I can look again but I don't think the USB are shorted, on back or the headers. The USB2.0 are powering up my portable monitor, so I don't think that's the problem. Does this L1085 run off the 12v rail?
      L1085BG maybe is 3,3v
      check :
      pin 1: 2.1V
      pin 2: 5V
      pin 3: 3.3 V
      it getting hot maybe has problem with 3v3 rail. check your led line, LAN and sound line, if all ok i think short on chipset.
      Attached Files
      Last edited by bbanana; 01-08-2023, 01:16 AM.

        Comment

        • nubie
          Senior Member
          • May 2010
          • 63
          #3
          Re: Gigabyte B460M DS3H blown standby regulator, hot 5v(?) Regulator

          Originally posted by bbanana
          check :
          pin 1: 2.1V
          pin 2: 5V
          pin 3: 3.3 V
          Pin1 is Ground, pin 2 is 12v pin 3 is 0.10V.

          I injected 3.3v from the PSU and smelled some burning. Getting another motherboard, same one, so maybe it can shed some light on the voltages.

            Comment

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