I have a kernel at my ftp site
ftp://204.57.142.148//NetBSD-1.5/

which should boot..
Notice you will have to use a serial console attached to com1
and scsi controllers not supported (uses nec710 not supported
by 'asc' driver). However you can plugin  an ISA/EISA ide
controller to the bus and that is supported.

Why the display controller and scsi controllers not supported
lack of hardware docs....

David Hopper wrote:

> I have two MIPS arc boxes that are a bit of a curiosity, about which I hope I
> can be enlightened.  They're extremely heavy (70 pounds or so) and quite large,
> about the size of two stacked desktops.  They are preproduction units circa
> 1993-94, but very close to the final hardware, from what I recall.  I _think_
> they are preproduction 2200's.  Here are the details:
>
> NEC Express RISCserver
> Model RT-4420-2767
> Dual-MIPS inside, on daughter cards labelled G8MZU REV. A3A
> Three huge core logic chips w/ heatsinks on motherboard (are these processors?)
> 7 EISA slots
> 1 EISA slot has a multi-IO board
> RAID bank, 8 drive slots
> 3 full-height expansion bays on top.
>
> If NetBSD doesn't run on this thing yet, I'd be glad to donate them both to the
> cause!  (Although I'm sure they are the only two left on the planet)  :^)
>
> A very old and crufty NT 3.5 or 4 is currently installed; maybe I'll fire that
> up one day and see what it tells me.
>
> Thanks all,
> David