I have a similar problem.  I have 24MB in a Dell 466SE (eisa)
that NetBSD only recognizes 16MB on.  The boot code sees
it, but the kernel doesn't for some reason.  I have had the
same problem since forever. (0.8?)  I hacked the 0.9 kernel
at one point to tell it I had 32MB of RAM (when I did!)
and it worked fine.
The boot code reads it from the BIOS settings right, so
why doesn't the kernel? 
Anyway, I'm not too concerned, but since I have a 1742 and
a 3c579, I *could* use all 24MB...  :-)

-Andrew

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