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sane100

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CMOS battery draining?

I have an ASUS P5B-VM DO motherboard, Intel Core 2 Duo chipset, four 1GB memory sticks and ASUS LCD monitor. My desktop computer was in hibernation overnight when there was a power outage for a few seconds. In the morning when I started the computer, the monitor says “No VGA’ (although it is connected to the DVI card). And I don’t hear the usual beep sound when booting the computer. Monitor and computer are not communicating.

The same thing happened about a month ago. Then I changed the CMOS battery (Lithium CR2032) and it worked fine since then until now.
What do you think is the problem?
 
Is my CMOS battery being drained out for some reason? If so, what is the solution?

Can you get any rechargeable CMOS batteries?

If I have to replace the motherboard, what will be a good replacement motherboard? ASUS discontinued this MB. If I have to replace the MB, it does not have to be micro or compact MB as I have a big  SMILDOON RAIDMAX case although I do not play games on my computer. I found out that it is not easy to find a motherboard with 4 DDR memory slots (240 pins?).
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Martin_J_Parker
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I've never seen a rechargeable CMOS battery or a charger for one that small.  Even if you could get one the charger would probably be expensive and you would need a charger because the motherboard wouldn't recharge it.

You may just have been unlucky with a battery which was close to expiry date.  They don't last forever and could have been old stock.  Try another one and check it has a long expiry date when you buy it.  If that fails agin then worry about replacing the motherboard.
You can pick one up a WalMart for less than $5.00
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I'll second the first poster's comments.

Try another battery and see how it goes.  Don't award any points to me.  I'm just backing up the poster's comments.
yep, could be a bad battery
>>  Is my CMOS battery being drained out for some reason? If so, what is the solution?   <<   since the draining is caused by the mobo, only way i know  is replacing the mobo

as for a replacement board - what do you want?  a compatible one, so you can just connect the disk to it, without fresh install? and use Ram and cpu ?
 
i had the same - and moved to the P5Q-VM with new cpu and ram
If you do try replacing the battery again make sure there's no hairs, dust or fluff around the battery holder which might be touching both +ve and -ve parts of the battery.  Even a small amount of conduction could theoretically cause a drain.
Be carefull taking the cmos battery out. Making sure you don't break the plastic holding it in the board.
I've only once seen a broken battery casing - caused by a class 1 bona fide idiot ex-colleague of mine who couldn't work out how to do it - so he tried prising the battery out with a small watch screwdriver while holding the opposite side of the holder with long nosed pliers!  He bought it in to me the next day to ask if I could fix it ...
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sane100

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nobus,
Thanks. But P5Q-VM is also discontinued and I could not find it anywhere on Internet!
argh . . and i need to replace mine as well..pc's move too fast..
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i replaced the CMOS battery. Nothing changed.
If I have to replace the motherboard I need one that can use my core2 Duo processor and the four 1 GB memory sticks if possible. I could not find any yet. Do you have any suggestions?
nobus is right - ebay is going to be your best bet now for a like for like replacement.  Finding new stock of a motherboard with 4 DIMM slots and that chipset is going to be difficult.

Mind you, a motherboard bundle with CPU and RAM isn't all that expensive these days:
http://www.novatech.co.uk/novatech/prods/motherboardbundles/Novatech/MBB-I5764G.html so If you are spending out on a mew motherboard then maybe it's worth getting an upgrade at the same time?
agreed, but would need a fresh install too..
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ASKER

Thanks.
I already checked on eBay. No Luck.
Also I could not find an upgrade combo at newegg.com (cheapest source I know) at a reasonable price. They have gigabite motherboards with 4 memory slots that may be compatible with my Core 2 Duo CPU. But the reviews of gigabite motherboards are not very encouraging.
i posted a link where it was on sale - did you not look at it?
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Yes, nobus. I did. There sale price is more expensive than newegg's regular prices on similar items! And that is beyond my budget now.
then upgrade it will become..
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I want to replace my motherboard with the same or a similar one so that I don't have to re-install Win 7 and all the other software.
then you'll have to keep looking i guess, unless you c&an grab this one (5.5$) :
http://shop.ebay.com/?_from=R40&_trksid=p5197.m570.l1313&_nkw=p5b-vm&_sacat=See-All-Categories
we can not repair a bad motherboard, only tell you it is bad.
it is not because you don't like the solution that it is not correct, so i'll object
ID:35106215 or ID:35135668
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Dear modus-_operandi,
I appreciate all your experts' trying to help me. None of their comments helped. None of them could point to the real problem. It seems neither the CMOS battery nor the motherboard has any problems. With the help of FREE web sites on Internet I was able to solve the problem. Putting this question on your web site was a foolish thing for me and a total waste of my valuable time.
Thank you.
and what was the solution then?
I'd like to know that as well.  This is the first you've mentioned that there was a solution.  
If it wasn't a duff battery and it wasn't a duff motherboard what would caused the battery to drain on only 3 months?
Did the battery actually keep draining?  If so, that's a physical effect.  
If that wasn't the problem why did replacing the battery appear to work in the first instance?
Was that just co-incidence?

The "experts" here are not infallible - they are merely a group of experienced people sharing their knowledge. When we do get things wrong it's useful to know why so that we can more accurately direct the next person with similar problems.  It's experience that makes somebody an "expert". It doesn't mean they know everything in their field.

These threads have built up to a large database of knowledge over the years.  There's still a lot that needs to be discovered or learned and it's a long way from perfect, but hundreds of people are helped every day - including many of us who contribute.  If we didn't manage to solve your problem then that's unfortunate, but I hope you'll have the good grace to tell us what did work so that we can more effectively help others in the future.
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I've never heard of defective memory draining a CMOS battery before.  I've had several duff memory modules in the past, both at home and work, but when I've seen memory problems it has either made the motherboard beep or caused problems when the machine is running.  

Replacing the CMOS battery really was the first obvious thing to try, even with the benefit of hindsight.  It's cheap, easy to do and was a likely culprit given the problem as explained.  Knowing that there had been a power outage it wasn't unreasonable to think that the motherboard might have been damaged when power came back.  Dodgy memory didn't seem to be a likely explanation at the time, certainly not in my experience of such things.

To be fair, if you went to the free forums knowing that it wasn't the motherboard or battery at fault then I'd have expected somebody to suggest trying the memory at that point.  There weren't really many options left by then!

Anyway, I'm really sorry to hear that it's caused you that much trouble. Many thanks for updating us.
As I said before, we can only help with those things that we have experienced.  I'm sure I won't forget this one in a hurry!

Regards,
Martin
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Martin,
I think you did not read my original question in full or misread it. I never said that CMOS battery was draining! I asked you people if that was a possibility.
Thanks.
AFAIK, the  ram has no direct connection with the Bios battery
so, i must conclude that something else "shorted " the battery - maybe a wire, or screw touching..
and changing the mobo cured it.
 BTW - just for giggles - did you run a memtest86+ on the "bad" ram?  curious to see the outcome
i also notived you said having 4 sticks in the board; correct? and the boar has only 4
then it can eene be a case of overloading the  ram bus
That's true - you did ask it as a question.  But it did seem to be a strong possibility as you'd replaced the battery and it had stopped working just a month later.  

When the replacement battery didn't work it would still seem likely that the motherboard would be at fault given that you weren't reporting any of the BIOS beeps which I've experienced in the past with bad RAM.
It's pretty bad luck to get no reaction at all from the motherboard with the bad ram installed.
and remember - we can only go on your post - not test anything
and we're not all very good at guessing..but it become s better - i still hope for the crystal ball this year..
Back to the modus operandi question:
it seems that he did indeed answer his own question in the end,
so that would seem to be option 4, ID: 35298459

Given the circumstances, I'd be equally happy with option number 1, except that I would prefer for the thread not to be deleted.  This thread may be useful for somebody experiencing similar problems in the future.