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Soviet Conscript
02-11-2010, 03:14 PM
well mostly have this old 486 pc computer up and running dispite one issue. if i don't power it on every day or so i get a
"CMOS battery low" "cmos type mismatch error" its not a fatal issue but it gets annoying haveing to reset my clock and bios all the time (detecting HD, setting up disk drives). now i know the fix may be pretty easy, replace the battery...except i can't find it...anywhere or a spot the battery may go for that matter. no nic-cad, no lithium and no little battery chip that says "Dallas" on it either. the sole thing i can find is a pin to connect an external battery but without knowing the voltage or polarity it is a bit desprate to just hook up a random one and hope for the best

my board is a ELITEGROUP COMPUTER SYSTEMS, INC. UM 486V AIO ver. 2.0

besides this page http://stason.org/TULARC/pc/motherboards/E/ELITEGROUP-COMPUTER-SYSTEMS-INC-486-UM-486V-AIO-122.html

i can't seem to find any other info on it. anyone happen to have the manual or know where i can dl one for this board?

Jorpho
02-11-2010, 08:04 PM
Can't say I've ever heard of those before.

http://www.techfuels.com/download-user-manual/23588-um4981-al0-ver-1-motherboard-user-manual.html sounds like a similar model, and mentions a 3.6 or 6V battery. eBay in turn suggests http://cgi.ebay.com/Lot-Of-25-Motherboard-Battteries-AA-3-6V-Tadiran-TL2100_W0QQitemZ200255239149QQcmdZViewItemQQptZLH_ DefaultDomain_0?hash=item2ea02473ed .

http://www.tadiran-shops.co.cc/tadiran-lithium.htm in turn links to http://www.amazon.com/exec/obidos/ASIN/B000V6W8GM/ref=nosim/macsho-20 , which looks like a pretty likely match.

Flack
02-12-2010, 06:58 AM
Toss up a picture of your mobo.

Soviet Conscript
02-12-2010, 10:57 PM
Pics of motherboard incomeing!

http://yfrog.com/i31010163j

http://yfrog.com/hq1010157j

http://yfrog.com/iz1010156tj

Ed Oscuro
02-13-2010, 02:54 AM
Huh, that's interesting. I wonder if it's the chip to the left of the AMIBIOS. Speaking of which, it looks like there's some rust above the chip above the AMIBIOS.

Flack
02-13-2010, 04:11 AM
According to this, there should be an external battery connected to J1. Yours seems to be missing?

http://stason.org/TULARC/pc/motherboards/E/ELITEGROUP-COMPUTER-SYSTEMS-INC-486-UM-486V-AIO.html

Soviet Conscript
02-13-2010, 08:32 AM
According to this, there should be an external battery connected to J1. Yours seems to be missing?

http://stason.org/TULARC/pc/motherboards/E/ELITEGROUP-COMPUTER-SYSTEMS-INC-486-UM-486V-AIO.html

yhea. i assumed external batterys were always just something optional or as backup. i've never seen a board that only had an external. i know where the pin for it is the problem is i have no idea what voltage battery i need or the polarity. i could just buy a random battery and guess but the effects of a wrong guess may be...unpleasent

it was suggested to me perhaps there is a conductor sort of like whats in a duo. since if i have it plugged in and start it up once or twice a day i won't get the error. only when i leave it off for over a day will i get the low CMOS error so something somewhere on this board is holding a small charge.


Huh, that's interesting. I wonder if it's the chip to the left of the AMIBIOS. Speaking of which, it looks like there's some rust above the chip above the AMIBIOS.

i was thinking that to, especially the smaller one but it looks nothing like the usual battery chips you see.

apogee_vgc
02-15-2010, 12:06 PM
I've had several that used an external rechargable that was velcroed to the side of the case and was enclosed in a black box approximately the size of a AA.

Soviet Conscript
02-15-2010, 09:10 PM
I've had several that used an external rechargable that was velcroed to the side of the case and was enclosed in a black box approximately the size of a AA.

i'm thinking thats the method on this one. i may just buy one plug it in and cross my fingers.........

Soviet Conscript
03-08-2010, 02:06 PM
http://www.tadiran-shops.co.cc/tadiran-lithium.htm in turn links to http://www.amazon.com/exec/obidos/ASIN/B000V6W8GM/ref=nosim/macsho-20 , which looks like a pretty likely match.

yhep, that seemed to do the trick. no more battery errors and bios settings seem to be keeping now. thanks jorpho.

just glad i guess the right way to connect it on the first try