I've just had the good fortune to be given a "slightly defective"
VAXserver 3400.  That is, a BA213 cabinet with a KA640, an 8MB MS650
module, a TQK70/TK70 kit, a KDA50 and two DSSI disks, both RF30.

The problem is that the startup test fails for the network interface.
I get the following messages:

[...] 07..06..05..
?5E 2 04 FF 00 0000
	[register dump here]
04..
?5F 2 0F FF 00 0001
	[register dump here]
03..
Normal operation not possible

>From playing with the monitor, I've found that test 5E is NI_memory,
and test 5F is NI_Test.  Now, I realize that this won't keep me from
running NetBSD/vax on the box, as long as I insert a network card and
a non-DSSI disk, and I've got both handy, but I'd like to repair this
KA640 if possible.  I'm guessing that 5F fails because 5E did.  Is it
reasonable to assume that there's a memory chip on the board that's
gone bad, and I can fix it by replacing said chip?  If someone with
technical documentation for the KA640 could give me some pointers, I'd
very much appreciate it!

Hmm.  If I'm right, I'll have to buy a smaller soldering iron, and
find something dead and disposable to start practising replacing
surface mounted components on...  :-)

-tih
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