Motherborad loosing BIOS settings - battery is fresh

  • Banned

    Hi again!

    I'm running pfsense ( ;-) ) on an Openvox IPC110, working fine. But the CMOS battery was empty, replaced it (soldering out/in), fine. With some of these boards. But 2 of them loose the BIOS settings when powered off, even with a fresh battery.

    Has anybody ANY idea what is going on here? I don't know how to solve this….

    Kind regards


  • You might want to check and see if the battery voltage is getting to appropriate pin on the RTC chip.

    I've seen cases where someone used the "ClearCMOS" jumber on a MB when the board was powered up and blew some protection circuitry, effectively disconnecting the battery from the chip - permanently.

  • Banned

    Hi and thanks!

    Any advice how to identify the RTC chip? Multimeter is onboard, so this is no problem… :-)

    kind regards


  • Could be a bit of a head scratcher, I'd look for a likely 104(?) pin IC not too far from the battery either on the top or bottom of the board.
    Google is your friend if you can read the IC markings

    You might get a little more info with the DMI-Decode package to give you a view from the OS POV.

    And perhaps check to make sure the ClearCMOS jumper isn't on (or the pins shorted)  ;)

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