NMI in System Mode on System V/386 3.0e

[David Kozinn]

I've got a problem on my System V/386 3.0e system where I seem to get
a "NMI in System Mode" pretty regularly after the system has been up
for a couple of minutes (or more.) The message only shows up once,
and after I get it the only symptom appears to be that the consoles'
scrolling (all of them, including the virtual consoles) are messed
up. Specifically, when the cursor is on the last line and the text is
supposed to scroll, instead of scrolling it wraps around to the top
of the screen again. (I've seen terminals that do this, but at least
they have the courtesy to clear each line before overwriting it!
<sigh>) Before I get the message, all works just fine.

Since the system documentation says that that message can occur
because of memory problems, I ran memory diagnostics and found no
problems. I also swapped out the video card and replaced it with
another and it made no difference. Incidentally, the machine is a
Compaq Deskpro 386 (16Mhz) with 4Mb of RAM and an 80287 coprocessor.

Aside from the screen problems, there are no other apparent symptoms,
and the system will run just fine for days after this problem occurs.
I'm totally at a loss. Can someone at least point me at something
that I can look at? Thanks in advance.         
-- 
         David Kozinn
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