CMOS Battery

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What would cause a new CMOS battery to go bad after only a week. Put a new battery in a friend’s system and within a week – clock was totally losing time. This is the 3rd battery we have installed.

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Interesting…

Unfortunatly, a bad CMOS battery isn’t the only cause for lost time. Here at work, we try to use the oldest systems possible to get the best results, (it all comes down to ca$h you know…) Well, we’ve recently come to find out that the strain we’re putting on our systems just by running complex processes, or multiple programs runs our system clocks down by an average of 4-6 minutes per day. (Being a very technically apt person, I run mine down 10-15 minutes in a given day.) For all intensive purposes, the only purpose of a CMOS battery is to keep the CMOS alive when the power’s off.

I would think that a strategically placed upgrade would likely resolve the bulk of your friend’s problems. I’d start with memory, and move on to processor speed if required. There are many contributing factors to these types of problems, but killing process hogs (Like the notorious Microsoft Office Quick Launch Bar, and Microsoft Find Fast) should have a good effect, and upgrades will likely keep the problem from happening again.

I hope this helps!

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OK – let’s start over – We have put in THREE batteries over a period of two months. Within a week, the clock was losing MASSIVE amounts of time. It was like as if something was draining the battery of power – not enough to screw up the CMOS but enough so that the clock simply does not keep time. This is a system which is used for email, internet surfing and minor word processing. Nothing intensive. I don’t think it is a case of “over use” of the resources. Thanks anyhow.

The system is a 300 MHZ, 128 MB RAM system running WIN 98 SE.

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This is certainly outside my areas of expertise, but I would guess that there is another problem besides the battery itself. Obviously replacing the battery is the first and cheapest alternative, but going through 3 batteries in two weeks does not make sense. Some batteries have been known to last beyond 5 years, so the battery must be a symptom, not the actual problem.

I would look deeper. Do you notice any symptoms besides the clock changing? If the battery was in fact dead the computer would not be able to retain its CMOS settings when powered down. If the CMOS settings are staying, I would look somewhere besides the battery.

I’m not sure exactly what piece of hardware keeps time – if it’s anything like a watch or standard clock there’s probably a quartz crystal somewhere in there. Maybe that’s become damaged – either from something physical, excessive heat, or just time.

Just my 2cents

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Hey Mark,

The dilemma is that when the new battery is installed, the clock keeps time wonderfully. But within a week, the clock starts to lose massive amounts of time. The CMOS settings however continue as set. So it seems the battery gets drained enough to affect the clock but not the CMOS settings. No other symptoms seem to be present. I think something is “draining” the power from the battery – perhaps the “quartz” that runs the clock????

Is there an alternative to the MB clock?

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It might have something to do with the issue you pointed out in post 182483 You might find in resolving that, your batteries will last longer. If it’s the same system you refer to there, it’s amazing it’s running at all after being hit by lightning…

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Hey Kel, we are talking about two entirely different systems. The parallel port issue is on a different system. I will double check the cards to see that they are properly seated (on the CMOS battery-challenged system).

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When you put in a new battery, you are re-initializing the clock.
Loss of time after that likely has nothing to do with the battery.

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I put in a new battery last night. All is well now. Time is right-on. Will see how long it lasts however.

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I wouldn’t discount my original suggestion, All versions of Windows, (Especially 98SE) are notorious pack-rats. At some point throughout the course of use, the system will become overly clogged with this ‘junk’, meaning that even web-browsing or simple tasks will become very process dependent. Check your resource availablility by right-clicking on ‘My Computer’ and selecting properties. It’s not an accurate measure, but if it’s under 70%, it’s time for some house-cleaning. Delete all Temporary files, run scandisk, and finally, defrag.

If you’re positive the above isn’t a problem, you might try the steps below.

Have you had your latest battery tested? Chances are, the place you bought it from has a voltmeter somewhere, (or a service desk with one) to see if the battery’s any good. if the volts on a standard 3v battery measure less than 2.5v, then bob’s your uncle! Replace the battery one more time (open the battery RIGHT THERE and have them test it. It’s highly unlikely that all three have been bad, but it is statistically possible. Also, check the following:

1. All boards and sockets are properly installed. A cocked expansion card or mis-aligned internal component can short out the bus, causing time-related problems.
2. Check the condition of the battery retainer itself.

If all this fails, I’d do some serious thinking about retiring the old beast. Any number of things can cause these problems, from damaged internal components (physical damage or damage over time) to the system’s becoming overheated, to the application problems outlined above. Conversely, it can’t be THAT expensive to pick up a motherboard for a 300mhz board from a used computer outlet. You might run away for the cost of replacing as many batteries over the next few months.

HTH

On another note, I don’t think that systems use quartz or any other traditional component to track time. I would think they use more of the digital clock technology than any traditional means. For more info on digital clock technology, click here.

I’m sure systems use the wavelength of the power supply to derive time, but some may have more accurate means of keeping track.

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I just checked the boards – they are all properly seated. As far as battery retainer itself, it looks fine but then, not sure what to look for.

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You’re just looking for anything bent out of place if it appears to be alright, chances are it’s good.

Advanced Power Managment was my last stop on this issue… sufficed to say, aside from the above, I’m at a loss!

300mhz systems aren’t exactly new, so it’s possible that the thing is just getting old… it’s a cop-out, I know, but as mentioned before, you should be able to pickup a used mobo for pretty cheap from a used systems peddler. The only true way to figure out what’s going on is to use some hefty diagnostics tools to test and re-test the system… I would be interested to know if the battery drains as quickly with the system not in use, (I.E. not even plugged in.) You’ll want to check to see if any wires have been pinched in the assembly of the case after the first battery was installed… anything grounding out to the case might prove problemattic.

Honestly trebor, without seeing it first hand, it’s hard to tell what might be going on.

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I’m way outta my league here, but isn’t there something called a “clock chip” built in to the motherboard that could possibly be malfunctioning?

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You know Al, I would think so too, but its most likely grafted to the board itself, meaning it would take a skilled solder artist or engineer to remove it.

In light of this thread, I think i’ll take apart my Linux box and tinker a bit..

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After tearing down my Linux box, I was able to confirm, in older systems at least, there is a clock chip but as I had feared it’s soldered to the board itself.

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Hi KEL,
thanks for all your input. Where can I find a reliable used MOBO peddler and how much would I be looking at for a replacement (used) MOBO.

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Hard to say Trebor, your best bet would be to check your local yellow pages for ‘Used Computers’. Couldn’t run more than $75US dollars (personally, I think that’s an extreme high, I wouldn’t pay more than $50), and it’s likely quite a bit cheaper than that! Just be wary of those hardware peddler’s who are out to rip people off… some of them are akin to used car dealers. If you make it clear that you are very technically inclined, you should be able to get a fair price.

Ebay is another good resource, people sell everything under the sun there.

Hope that helps!

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We live in a small town in Arkansas. No used dealers here or anywhere close. Guess I will have to do a google search and check EBAY.

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Kel,
I would agree and disagree with you on some of the items.
I don’t believe that resource loading or piles of “junk” files have anything at all to do with the condition of the CMOS battery. The battery in the PC, as in any other device that uses a small “nickel” battery, is a device to hold settings (and clocks) in place while the unit is powered off. When the main power is applied, the backup battery is switched out of the circuit(s) and does not have a drain applied on it until it again goes to power off condition. This, of course, is the normal operation unless there is a defect, in this case the clock circuits, that will consume more current than is normal to hold everything intact.
The suggestion to check the “before and after” voltage of the battery to determine if it is actually the battery itself is a good one. If you get the battery from the same source, they may have had these sitting around for enough time to exceed the “shelf” life of the battery, and they may be low voltage right out of the package. That being the case, most mobos use a small digital timer chip for the system clock, and depending on the design parameters for that chip, it may be that it will start to degrade timing after only a short period of battery use. With any electronic design, the voltage parameters are variable. Some things tolerate a large voltage swing, others do not.
The other possibility is a problem in the clock circuit itself, if indeed the battery is being “drained” in such a short period. Yes, check the battery holder contacts to make sure there is no corrosion where the battery fits into the holder. A good tool to use here is called a burnishing tool, which is a very lightly abrasive blade used to shine up the contact areas. Don’t use emory,it’s conductive!
Also, if the above is true, then my best guess is that the clock chip or it’s circuitry are “going south, to retirement” Usually not worth attempting to repair.

Bob

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Bob,

I think you may have misread some of my points. I am not saying that system ‘junk’ has anything to do with the condition of the CMOS battery. However, this residual ‘junk’ that all versions of windows inherently create, can lead to the same types of symptoms as a failing CMOS battery. There comes a point where the system just can’t handle the amount of information it has to tread through. It occurs more often than not on older systems, where new programs and processes are built to comfortably run on faster systems. When you add the variable of custom applications built within a given organization, the effects on the timestamp of the system can be quite profound. It doesn’t happen everywhere, but here at work, our IT department has run things in such ways that correcting login scripts are required to adjust system times at startup.

Your other assessments are good indications of the points I was trying to get across. It’s been a little while since I cracked the case on anything other than the transmission on my aging VW, so thanks for filling in the details where things have become fuzzy!

Warmest Regards,

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Do you use Norton Auntie Virus?

If so, do you have the latest SOFTWARE, not just virus def, updates?

There was a bug in a few versions of NAV that caused the lock to lose time.
Symantec finally issued a fix.

You could also lose time if, say, automatic power management is enabled.

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Yes, I do have Norton – have updated the defs and the software. Just installed Norton Systemworks 2003. I have set the Power Mgmt to DISABLE in the BIOS.

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