Hello,

> My case claims to be a 4000/90, yet my CPU is a KA46. Looking through

At power-up the POST routine will display CPU type (KA46 or KA49 in your
case) at the top of the screen. What does it say ?

CPU is identified by SID register (and SID Extension field in ROM). To
see SID type

>>> e/i 3e

and to see SIDex type

>>> e/l/p 20040004

But the result will be same (= whatever POST says is in your box) so
this is just a waster of time.

> I have thought that the /90s were KA49 CPUs, and the /60s were the KA46.

You are correct.

> Oddly, the case also claims that it's a serious BA46A ... that doesn't
> seem to fit with the 4000/90 sticker. Is there maybe a piece of Vax
> history that I don't know that would explain this? It's a mystery that
> I'd love to solve.

BA46 is enclosure type. BA46A is the "standard" (horizontal) and "B"
variant has small leggs added to it for vertical positioning. Both
4000/60 and 4000/9x came in BA46 enclosure, BA46 doesn't mean it must be
KA46 inside (and there is no "BA49" for 4000/90, same BA46 is used).
Read what POST says, if it's KA46 then you've got KA46, if it's KA49
then you've got KA49, it doesn't get any simpler than that.

>>> show config 

will again print out the KAxx line, as well as the rest of components.
If you have 4000/60 you'll probably have LCG graphics (unless it's been
replaced) and on 4000/90 you'd have LCSPX. Another difference is the
audio device POST, on 4000/60 it is shorter (only emits three tones
IIRC) and on 4000/90 it's about twice as long, first emitting  same
three or four tones and then a prolonged beep.

Blaz Antonic
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