26 May
2021
26 May
'21
9:14 p.m.
On May 26, 2021, at 3:38 PM, Jonathan Stone <kiwi_jonathan at yahoo.com> wrote:
On Wednesday, May 26, 2021, 02:35:32 PM PDT, Zane
Healy via cctalk <cctalk at classiccmp.org> wrote:
[....]
two points:
1. MS650-AA 8mb modules from a KA650 will work in a KA640. They won't work with a
KA655 or a kA660 (or a KN210_. Those need the MS650-BA, or the 16MB MS650-BB, or the
third-party 32MB modules. So if your KA640 is dead and you want to upgrade, you will
likely need new memory, too. (You likely know this already.)
THANK YOU! I didn?t realize this. I?m not sure what the modules are in the MicroVAX 3,
or how big they are. They?re in a computer rack that requires some effort to access, so I
haven?t gotten to them yet. It sounds like I?d best have a look at RAM...
2. A few times over the last year, I've read an
online service manual detailing how to turn a BA430 into a BA400X.
That manual describes pulling the CPU and inserting the DSSI"paddle board" in
the first slot. That manual should be. useful in understanding your nonstandard chassis.
However, if I recall correctly, I think you need to remove the "paddle board"
and put the CPU into the first slot, for bus-termination reasons. The memory modules need
to move one slot over to match. I don't know if that will help with your diag
failures, but it seems worth trying.
Do you happen to know what Manual this is? I?ve spent a lot of the last couple days
reading up on the BA430/B400X, and the KA640/KA660.
Zane