CMos battery Malfunctioning - Page 2

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Re: CMos battery Malfunctioning

Usually; not always.  Motherboard problems can cause RTC clock problems
(some of these are problems charging a rechargeable CMOS battery).

The computer has no way of knowing what time zone you are in.  Further,
and quite significantly, when IBM designed the original PC back in 1980,
they provided no place in CMOS memory to store the time zone.
Consequently, if the time is lost, if CMOS memory is lost or if Windows
is reinstalled, the time zone will be lost also.

Roy wrote:
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Re: CMos battery Malfunctioning

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That might be the reason ,......Meaning
the battery is not necessarily weakened....

That partcular laptop have its corrupted hard drive replaced by a new
one but it did not
exhibit such time lag  immediately after.....
Rather the fault came out almost a month after......

I have asked other users of the same laptop type and brand and they
said to me
that they never experienced such  clock fault I am having
now...Therefore this led me
to think that its not entirely the weakened Battery that could be the

Re: CMos battery Malfunctioning

Roy typed on Wed, 20 May 2009 12:36:50 -0700 (PDT):
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Hi Roy! It could be a few things.

1) Software (rare)
2) CMOS battery is now charging
3) Clock/CMOS is running off of AC instead of battery

Asus EEE PC 701G4 ~ 2GB RAM ~ 16GB-SDHC
Windows XP SP2

Re: CMos battery Malfunctioning

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Hmmm, is there any software that can do such fluctuation...?
Does it mean also that charging is not consistent ....may I know how
does that happen..?

Re: CMos battery Malfunctioning

Roy wrote:
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Some softwares re-program the clock.
I personally wrote a few,for microsecond timing, or sound
production from the internal speaker.
And if such a program is terminated by ctrl/break, the clock
might not be restored properly.

Re: CMos battery Malfunctioning

Roy wrote on Thu, 21 May 2009 15:23:45 -0700 (PDT):
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Hi Roy! If it is software, it is easy to check. Just boot up to the POST
screen (Setup). And check the clock. If ok, turn off and do the same at
a later date. If always okay, it is the software most likely.

Charging? We don't even know if it uses a rechargeable battery for the
clock. And giving the battery a break by having it on AC could cause the
battery to recover a bit. And we don't know that either. Lots of if's Roy.

Asus EEE PC 701G4 ~ 1GB RAM ~ 16GB-SDHC
Xandros Linux

Re: CMos battery Malfunctioning

It is almost certainly the battery.  The life of these batteries,
whether rechargeable or not, varies widely.  Some fail after two years,
others are still going after 10 years (in the SAME laptop model ....).

The level of difficulty to replace also varies widely.  Most laptops do
require disassembly down to the motherboard (this is pretty major,
usually one to three dozen screws and you have to know what you are
doing).  I was working on a Toshiba A105 last week and ... HORRORS ...
the CMOS battery is SOLDERED to the motherboard (not clear if it is a
very long life lithium or a rechargeable, but in my view, this was poor

Comment:  We have an electronic bathroom scale with a battery soldered
to it's circuit board (I had opened it once).  The manufacturer's intent
was that when the battery dies, you replace the scale.  The battery is a
standard lithium coin cell, the same type as desktop motherboards use
(CR2032 or 2025 or 2016 ... the number was visible on it) but with
solder tabs.  The bathroom scale works fine.  It was purchased in 1991.
  So it's possible for batteries to last a LONG time.  But, that said, I
don't like a semi non-replaceable CMOS battery on a computer
motherboard.  [As to the bathroom scale, my intent will be to replace
the battery, possibly with a socketed version of the same cell type if I
can't find an exact solder tab replacement.]

Roy wrote:
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