On May 26, 2021, at 3:38 PM, Jonathan Stone <[email protected]> wrote: > On Wednesday, May 26, 2021, 02:35:32 PM PDT, Zane Healy via cctalk > <[email protected]> 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
