new CMOS battery dies every 1 1/2 months

[CanDMan]

My motherboard is eating batteries for breakfast, i would think that means that these batteries are usually recharged by the motherboard and that this it not happening on mine. Further complicating things is the fact that the cmos will lose settings on reboot unless there is a fresh battery in (warm and cold boots), so i can't start the system at all without feeding it batteries. i'm getting to the point where i can't keep feeding it batteries, does anyone know of a fix? or a way to circumvent the need for a battery? is there something i can check to determine if it's getting the power it needs? (i checked the voltage between the leads for the battery connectors (*not the battery itself*)and didn't get any voltage) ...am i supposed to have some voltage there?

I'm looking for a cheap fix, (maybe an isa board cmos replacement? ever hear of that?) replacing the motherboard at this time would mean a whole world of other upgrades because this is an older system (AMD K6/2 233 with an appitite for CR2032 batteries). I'd appreciate any help. thanx.

[zevon8]

That's a lithium battery, and it should last a couple years.
I've seen some go 5 or 6 years. They are not rechargeable BTW. That is the right battery, isnt it ? or did a previous owner stick the wrong one in? I'm thinkin something like a jumper for an external battery is off, in the wrong position, or faulty somehow, and the CMOS is just not getting properly powered. Ok, heres a reach, but look and see if the jumper for CMOS battery voltage is OK, and that the contact springs in the battery holder are clean, and making good connection, and have not come loose from the mainboard.

[CanDMan]

zevon8, thanx for those tips, I checked the jumpers and there is no jumper selection for an external battery. I think the most likely explanation is that the contacts may be loose, but would this Drain the battery in a couple months? ...yes, these litium batteries should last many years, that's why it's driving me nuts ...i'm just not sure if bad contacts would drain the battery tho. Does anyone know what would need to be happening for a battery that should last several years to last only months?

i guess i should also say that while the battery has enough voltage it doesn't give me a problem, it's specifically that the battery drains after only 1 1/2-3 mos.

[zevon8]

I should have explained, sorry. If there are bad connections, the battery voltage will be lost across the connection, and not delivered to the load - like a middle man taking his cut of the profit before passing it on. So what happens is that the battery is only marginally dropping in output, but the loss due to the connection drops the battery voltage at the load to a low enough point that it will not sustain the CMOS chip. The problem is that the battery often drives a small pseudo switching supply to boost the voltage up to 5 or 6 volts, and any drop may not let it function.

3v(new batt.) - .2v(loss)= 2.8v(at CMOS) maybe ok
2.8v(old batt) - .2v(loss)= 2.6v(at CMOS) maybe NOT ok

If the connections look ok ( use a loupe or 10X lens),
maybe there is something wrong with the CMOS supply cicuits. could you try a bigger capacity (ampere/hour rating, NOT voltage) battery? something like a 3v camera battery (CR17345), just attach the wires to the holder by taping them around a taped up CR20332 battery to act as a filler.