On 28-May-18 5:30 PM, Graeme wrote:
In message , Chris Green
writes

They were mostly non-rechargable button cells but I did have one that
had a rechargeable battery.Â* Not usually too difficult to replace,
just take a look inside at the motherboard and it should be pretty
obvious.

OK, I'm missing the obvious.Â* The case is off, and I am looking for a
silver button battery, probably about the six of a sixpence.Â* Could it
be entirely different?

Very old PC's 286/386 had batteries that were about 2" long, 1/2"
square, had a long lead and plugged in on 4 pin plug. Usually Velcroed
to something, if built by ****s the bios chip otherwise the side of the
PSU. I think these were lithium.

A nicd would be 3 cells in a shrink jacket about 3/8" dia and 3/8" long.
The cells are stacked on their side, with tags at the ends that solder
into the board. I've got a vesa bus socket 3 motherboard (486/Amd586)
with this type of battery on it. Battery has a green jacket but I think
I've seen black, red, blue and yellow as well.

Silver button cell lithium was introduced I think about Pentium MMX and
socket 7. But as I don't have any socket 3/4/5/6 boards it's a bit hard
to tell.