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Death_Knight
05-29-05, 04:41 AM
Is there anyway to check the power of the battery through BIOS?
Captain Slug
05-29-05, 07:43 AM
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.
Feydd
05-29-05, 11:04 AM
It's something along the lines of "CMOS Checksum error, load optomized defaults?" If you see that you know you need a new battery.
Kill_A._Byte
05-29-05, 11:21 AM
Sometimes the odvious makes you feel so dumb... :bang head Every time I unplug I have thet problem. I just figured it was a new board so the bat would be good.
Thanks for pointing out the odvious.
Killa
wdeep4
05-29-05, 11:50 AM
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.
Diggrr
05-29-05, 08:51 PM
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.
Gnufsh
05-29-05, 11:40 PM
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?
Death_Knight
05-30-05, 06:49 AM
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?
Gnufsh
05-30-05, 07:02 AM
I assume so. lm_sensors can read mine from linux.
NetworkGuru
05-30-05, 09:04 AM
Does MBM or other software that operate on windows able to detect the battery lifespan?

SpeedFan is able to read my CMOS batteries output voltage.
Death_Knight
05-30-05, 02:00 PM
SpeedFan is able to read my CMOS batteries output voltage.

Can provide some screenshots, i am noob on pc hardware :bang head
NetworkGuru
05-30-05, 02:14 PM
Can provide some screenshots, i am noob on pc hardware :bang head

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.
Death_Knight
05-30-05, 02:27 PM
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.
Zulu-1
05-30-05, 02:27 PM
yeah... i can monitor my battary's voltage too....
Death_Knight
05-30-05, 02:33 PM
Asked this question around some forums, they told me to get a voltmeter to check the battery lifespan. LOL
SolidxSnake
05-30-05, 02:34 PM
well, it'll check the battery's voltage. Not lifespan, however ;)
Gnufsh
05-30-05, 03:27 PM
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.
Kill_A._Byte
05-30-05, 08:55 PM
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?
Death_Knight
05-30-05, 10:52 PM
When should we change the battery? When VBATT falls below 2V ?
Gnufsh
05-31-05, 12:26 AM
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.