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Check CMOS battery

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Nope. A weak or dead CMOS battery will result in your settings being lost every time you computer is unplugged, and that's your only indicator.
 
It's something along the lines of "CMOS Checksum error, load optomized defaults?" If you see that you know you need a new battery.
 
Another symptom of a weak cmos battery is if your system clock is consistently losing time.

I've bought dozens of new motherboards over the years, and I've never had one come with a bad battery. That's got to be quite rare.

A cmos battery will typically outlive your rig. I've seen 10+ y/o pieces of junk still running with the original cmos battery.
 
I've yet to own an Abit (3 so far) that won't lose settings being unplugged for a day or two. But at least you can pick up the batteries for cheap at the computer show.

One thing I've noticed though is that some contacts have a hard time getting over a couple of finger prints...pull the battery lately to clear bios? Free to check.
It might help a weak battery to make it until payday/trip to town.
 
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Many on board sensor chips can monitor the battery's voltage (mine does). A drop in output voltage could signal that the battery may be needing replacement before settings are lost. I don't remember exactly what the voltage should be. 3.something?
 
Gnufsh said:
Many on board sensor chips can monitor the battery's voltage (mine does). A drop in output voltage could signal that the battery may be needing replacement before settings are lost. I don't remember exactly what the voltage should be. 3.something?

Does MBM or other software that operate on windows able to detect the battery lifespan?
 
NetworkGuru said:
Go here. http://www.almico.com/speedfan.php
Download speedfan.
Install speedfan.
Run speedfan.
Should look something like this. http://www.madenlief.demon.nl/speedfan.jpg
If I'm not mistaken, the reading for the CMOS battery is near the bottom where it says Vbat.

oh, VBAT represents the lifespan of the battery? Because i came across this in the BIOS, google for some results still not sure what it is.. I think mine show about 2.9v.
 
Asked this question around some forums, they told me to get a voltmeter to check the battery lifespan. LOL
 
exactly, voltage is not the same as lifespan. It can be an indicator of when you need to replace the battery, however. My VBat is 3.17 right now. If I see it start to drop off significantly, I'll think about replacing it.
 
O.K. I downloaded speedfan, installed...etc...etc...
It shows 0V on the bat, so I run to the drug store and get a new one, it still shows 0V on the bat. So I figure it dosn't read my board right. Then I look at the other voltages and I'm getting fluctuating readings like crazy on the -5V (-1.44-1.64-0.29) the -12V is reading -9.07V, the +5V is at 4.68V, The +12V is at 10.43V, the +3.3V is +3.01V, Vcore1 is right on 1.66V, Vcore2 (didn't know I had one.) is 3.31. I hope program has a hard time with my board, and it's not my PSU. (I fell for the flashy chrome box and the modular UV cables. :shrug: ) The hardware monitor that came with the board reads +3.3V at 3.29V to 3.31V, +12V is at 12.22, +5V at 5.05V.
What do ya think?
 
Sounds like speedfan is not correctly reading your voltages. You could always use a meter to manually measure the battery voltage.

I'm not sure what voltage on the battery you need to maintain the cmos. If mine fell to 2v, however, I would replace it. Basically, a rapid drop in voltage signals that a battery is nearing the end of its lifespan.
 
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