I replaced the battery back in November in my ASUS ISA-386U3 motherboard.
Looking at the time, it was still showing the date as the end of 2019!
Voltage measures 3.6V exactly and the motherboard definitely is not trying to charge the battery (looks like the charge jumper was never installed in factory)
Any ideas? Hopefully its nothing too difficult to repair. Was reading it could be a crystal at fault?
I've read about this problem a few times. The voltage might be too low to keep the clock running. Was the original battery also 3.6V?
This search finds a few topics, but it's hard to wade through 😀 search.php?keywords=bios+battery+clock
EDIT: reworded
1982 to 2001
Cyrix200+ wrote on 2020-08-03, 10:03:I've read about this problem a few times. The voltage might be too low to keep the clock running. Was the original battery also 3.6V?
This search finds a few topics, but it's hard to wade through 😀 search.php?keywords=bios+battery+clock
EDIT: reworded
Ive been doing a bit of reading.
Worst case scenario it could be an IC on the board?
crystals and diodes seem other common issues.
I have no idea what voltage it should be, as the manual does not say.
What I do know is its not charging the battery, and the last owner had 2x AAA cells connected for 3V.
When in the CMOS setup, the clock seems to be counting a bit erratic and not at a constant rate.
nzoomed wrote on 2020-08-03, 10:11:Ive been doing a bit of reading. Worst case scenario it could be an IC on the board? crystals and diodes seem other common issue […]
Cyrix200+ wrote on 2020-08-03, 10:03:I've read about this problem a few times. The voltage might be too low to keep the clock running. Was the original battery also 3.6V?
This search finds a few topics, but it's hard to wade through 😀 search.php?keywords=bios+battery+clock
EDIT: reworded
Ive been doing a bit of reading.
Worst case scenario it could be an IC on the board?
crystals and diodes seem other common issues.
I have no idea what voltage it should be, as the manual does not say.
What I do know is its not charging the battery, and the last owner had 2x AAA cells connected for 3V.When in the CMOS setup, the clock seems to be counting a bit erratic and not at a constant rate.
Could be all those things, but the battery seems to be the logic thing to check first 😀
Deksor has the same board, he might be able to give some information?: 386DX40, slow performance ?
I found you post on the board, it seems to be in very good shape!
I feel that the original battery did need to be charged by the board. And if there is no jumper, did you change anything to prevent charging?
Is trying another battery an option? Maybe 2x (or even 3x) AA or AAA?
You did solder in the wires right? Not just the hot glue? (please don't be offended by the question haha)
1982 to 2001
Cyrix200+ wrote on 2020-08-03, 10:43:Could be all those things, but the battery seems to be the logic thing to check first :) […]
nzoomed wrote on 2020-08-03, 10:11:Ive been doing a bit of reading. Worst case scenario it could be an IC on the board? crystals and diodes seem other common issue […]
Cyrix200+ wrote on 2020-08-03, 10:03:I've read about this problem a few times. The voltage might be too low to keep the clock running. Was the original battery also 3.6V?
This search finds a few topics, but it's hard to wade through 😀 search.php?keywords=bios+battery+clock
EDIT: reworded
Ive been doing a bit of reading.
Worst case scenario it could be an IC on the board?
crystals and diodes seem other common issues.
I have no idea what voltage it should be, as the manual does not say.
What I do know is its not charging the battery, and the last owner had 2x AAA cells connected for 3V.When in the CMOS setup, the clock seems to be counting a bit erratic and not at a constant rate.
Could be all those things, but the battery seems to be the logic thing to check first 😀
Deksor has the same board, he might be able to give some information?: 386DX40, slow performance ?
I found you post on the board, it seems to be in very good shape!
I feel that the original battery did need to be charged by the board. And if there is no jumper, did you change anything to prevent charging?
Is trying another battery an option? Maybe 2x (or even 3x) AA or AAA?
You did solder in the wires right? Not just the hot glue? (please don't be offended by the question haha)
mt777 has the same board too I think.
It is indeed a very nice board. I hope Its an easy fix, needless to say it works fine and is worth fixing.
I did nothing to prevent charging, the last owner had soldered a battery holder in the same way ive done, but used only 2xAAA, so im assuming it worked with no issues.
There is a jumper position marked jbatt where the battery goes, but the actual jumper pins were never installed at factory, which means it wasnt ever charging a nicad.
I tested with a multimeter and its definitely not putting out power to charge the cell (i think it would have exploded by now 🤣)
Some boards require 4.5V but dont want to screw things up. I feel 3.6V should have worked.
Battery is still measuring 3.6V exactly.
yup, the wires are soldered, i just used the hot glue to stop them breaking off.
