🚀 go-pugleaf

I've been mucking around with my mono NeXTstation, trying to add memory.
I initially had eight 8bit x 1M 100ns SIMMs in there (I was a bit surprised
to notice the 100ns bit -- I thought one should have 70ns to get max speed
from the speed-detecting memory system).

I removed all SIMMs, then put in four 9bit x 4M 70ns SIMMs.  All is well,
16M of memory.  I add in four of the old SIMMs to get an even 20M of memory.
It works, but the memory test says 100ns.

I guess it has to run all banks at the same speed.  I pull the old SIMMs
to see if this is true.  Exception 2.  Exception 3.  What's all this ?
I put the old SIMMs back in place.  20M of 100ns memory, again.

So, how the %$*#@! is one supposed to configure this thing ?
What's supposed to work, and what's not ?  Is there a section in the
built-in manual (or NeXTanswers) that deals with this ?

PS. For some reason, the power key doesn't work from the ROM monitor.
It tries to shutdown, then dies with some obscure exception.
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