CMOS battery dying. What are the symptoms?

Discussion in 'Computer Help' started by imported_Scythe, Feb 18, 2005.

  1. imported_Scythe

    imported_Scythe Junior Member

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    I've been trying to isolate a problem, and it's getting no where. Everything passes stess tests, mem checks, hard drive tests etc.

    If the CMOS battery was going bad, what kind of symptoms **could** be occuring, in your experience? I guess I could just check it wtih a volt meter, but still curious.
     
  2. imported_hobbes

    imported_hobbes Junior Member

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    I do not think that the cmos battery has any function other than being the backup supply for the bootup RAM. This stores all your boot preferences even when the computer power supply is off. In case it has gone bad, while booting you should get the prompt that boot defaults are being used...
    The way to check it is to make changes in the boot setup and shutdown. If you see the changes next time you startup, the cell should be fine.

    Please do correct me if I am wrong! :)
     
  3. Calin

    Calin Diamond Member

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    Your computer will loose its time and date after prolonged (or less prolonged) storage (no power cord)
    I think (with an ATX power supply) the CMOS is powered from the power supply if it is under tension (plugged in a socket)
     
  4. jackschmittusa

    jackschmittusa Diamond Member

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    First symptom is usually a "checksum error" at bootup, prompting to "press F1 to continue" or "F2 to enter setup". Then you may notice the time, then date get behind.
     
  5. LTC8K6

    LTC8K6 Lifer

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    A new one is only what, $1.98? Put a new one in and then you'll know.

    An early symptom of a CMOS battery getting weak is a clock that runs fast.