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mattd1979
July 31st, 2009, 04:25 PM
My AST Premmia MX P/60 (first gen pentium) computer is missing the CMOS battery. The battery pack configuration consists of 3 AA rechargable batteries. I Use to have the battery pack put removed it a long time ago because it was bad and I misplaced it. The problem now is finding a replacement. I decided to use a 3.6V battery pack from a cordless phone but I have to determine which pins to connect the battery too. There are 3 pins, 2 close together and 1 by itself. I don't want to connect it backwards. I tried using a volt meter but I can't really get any good readings. All 3 pins give me a reading of what looks like .83 millivolts I believe.

lutiana
July 31st, 2009, 05:35 PM
Can you post a picture?

Chuck(G)
July 31st, 2009, 06:01 PM
My AST Premmia MX P/60 (first gen pentium) computer is missing the CMOS battery. The battery pack configuration consists of 3 AA rechargable batteries. I Use to have the battery pack put removed it a long time ago because it was bad and I misplaced it. The problem now is finding a replacement. I decided to use a 3.6V battery pack from a cordless phone but I have to determine which pins to connect the battery too. There are 3 pins, 2 close together and 1 by itself. I don't want to connect it backwards. I tried using a volt meter but I can't really get any good readings. All 3 pins give me a reading of what looks like .83 millivolts I believe.

The negative pin will have continuity with the power supply ground (black wires on the motherboard power connector (and probably the lands around any mounting holes). Use your ohmmeter. The other pin is the positive end. 3 AA alkaline cells with a series diode delivers about 3.6V right on the nose.


I like to use plain old AA-size alkaline cells with a series-connected diode (a 1N4002 or the like is fine). I just replace the batteries every few years as needed (and I mount the battery holder outside the case in case of leakage.

mattd1979
July 31st, 2009, 07:01 PM
http://i571.photobucket.com/albums/ss159/mattd1979/cmosbatteryconnector.jpg

The connector is at the lower right corner of the picture.

Chuck(G)
July 31st, 2009, 07:25 PM
It looks like the stanard 286/386/486 external battery connector. 1 = +, 2 = NC, 3 and 4 = -. Use your continuity tester and see if pins 3 and 4 are connected together. If so, you've got your answer.

mattd1979
July 31st, 2009, 07:35 PM
Yep that was it. You got it. Thanks very much

SaVawn
August 31st, 2009, 01:06 AM
Hmm...That is what I was thinking, but Ive pretty much been having this problem since I first purchased it. Does anyone out there have a WD external drive?????

Chuck(G)
August 31st, 2009, 04:32 PM
I'm having trouble following your statement with the topic of the thread. Care to elaborate? Thanks...