First post, by naujoks
I have a board with a 386DX 40MHz, whose CMOS chip only remembers the date and time but no other settings (board info: https://theretroweb.com/motherboards/s/j-bond-a340c-h )
The board was badly damaged by battery leakage but I've got it to work again.
I replaced the original barrel battery for a CR2032 cell (with diode). The board also has contacts for an external battery, which I also tried, but the result is the same.
When starting the board, the BIOS reports CMOS battery state low. Once I have the board running, System Information lists the CMOS battery as functioning.
Amongst the parts which I had to replace were the diodes D1-D4, which are connected to the BIOS battery circuitry. I didn't have any information on the types of didoes so I guessed replacing them with bog standard 1Ny148 would be ok, but perhaps they need to be something else?
Any ideas what else might be the problem?