It is extremely unlikely that anything was wrong with the little coin-shaped
battery. However, you can always test it by putting in another new one. I
just bought some packs of these at Target and they were about $4 for a pack
of two batteries.

If a new battery doesn't help, your motherboard is dying.

Malke

Use a tester to check the battery voltage, if less than 3v, it is dead.
If this happens with another new one from a different source (not old
stock), there is a motherboard issue. (look for swollen electrolytic
capacitors on the motherboard).

One reason for a CMOS battery to run down, is if the clear CMOS jumper
is in the wrong position. But you'd have some other symptoms if
that was the case, like losing your settings.

The CR2032 should be able to maintain 3.0V or greater for most of
its life. At roughly 2.4V, then the ability to power the CMOS would
be getting a bit dicey.

The CMOS circuitry may draw around 10 microamps, to there
is no real load to speak of. The battery should last 3 years or so,
if the computer is stored in the garage (i.e. running on battery
constantly). If the computer is always plugged in and left
switched ON (so +5VSB is available), then the PSU supplies
the 10 microamps. In that case, the battery lasts for its shelf life,
which could be up to 10 years.

And there ARE bad batteries at some of the lower volume stores.
I picked a couple silver oxide up at an actual "battery store"
in the mall, and they died after a couple days. So there is crap being
offered for sale. Since then, I look for high volume sellers.

Batteries can be counterfeit, and the vendor might not even
know. There may be very little working material on the
inside, for example. Even a Japanese battery might be
faked, by someone in China. All it takes is a retailer
who thinks they're getting a "bargain".

   Paul