I've been playing with a 3/160.  When I first got my hands on it,
it would boot okay, but the tape drive (SCSI) wouldn't work and it was
shutting down due to over heating.  I replaced the SCSI ribbon cable
(which was badly chewed up) and the bad fan in the power supply.  After
that, I had booting problems.  At some point during autoconfiguration,
it would start printing, level 3 interrupt, continuously.  This is the
vector for the multiport serial card.  I recall having problems with
that in the past if the cables weren't connected.  So, I pulled the
card and dug around on the net to find out how to set the VME jumpers.
At the same time, I temporarily pulled the SCSI card (leaving CPU,
memory, and SMD controller {xyc0}).  This still didn't solve my
problem.  So, I decided to try booting NetBSD on it (the machine has
SunOS 4.0.3 loaded)...

     After scrounging through the documentation I could find and some
experimenting, I managed to have some success netbooting it.  The first
major stumbling block I had was that the NetBSD/sun3 1.4.2 RAMDISK
kernel is missing the ramdisk image, as evidenced by the complaint
about not having /dev/console and the size of the file.  I solved this
by using the 1.4 RAMDISK kernel.  After that, I managed to get to the
ssh> prompt.  At this point, I NFS mounted my diskless boot area and
attempted to 'dd' the 1.4.2 miniroot onto xy0b (400M SMD Fujitsu
Eagle).  As soon as I attempted this, it popped up a message that said
something like "autovec: unexpected csr 0" (guess I should have written
it down).  Anyways, does anybody have any suggestions?