vaxstation ii machine check & diags efficacy

[Glen Slick]

On Wed, Jun 19, 2019 at 12:24 PM r.stricklin via cctalk
<cctalk at classiccmp.org> wrote:
>
> It's a VAXstation II/GPX. I'm trying to install VMS 5.5 (from CD if it matters; there is a CMD CQD-200 or -220 as the only storage controller) and routinely getting machine check exceptions.
>
> Standalone backup always boots. Sometimes I get an exception the moment I hit <enter> on a restore; sometimes in the middle of the restore, sometimes it runs to successful completion.
>
> VMS never boots. Sometimes I get as far as the date prompt (I took out the battery), sometimes it gets a little farther, frequently it's before anything appears on the console at all.
>
> The exceptions booting VMS occur the same if I attach another disk with VMS 5.5 already installed; if I replace the KA630 and M7609 with a KA655 and M7622, it all seems to run fine.
>
> The KA630 power-on diagnostics all pass, but... it smells like a memory fault to me. What are the odds there could be a memory fault that isn't caught by the diags?
>
> ok
> bear.

Maybe try running the MDM (MicroVAX Diagnostic Monitor) diagnostics
and see if they detect any issues that the power-on diagnostics do not
detect.

I have a bootable image of this version, which you should be able to
'dd' to a disk you can then attach to your CMD CQD-220,

uVDOS V4.0 built on 23-mar-1993  12:01

MicroVAX Diagnostic Monitor    Release 139   Version V5.0

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