The board claims to be I/O register and command compatible
the the adaptec AHA 1540/1542 boards and by god it is :-)
My machine booted happily using the adaptec boot floppy
and is now -current.  It might be worth mentioning
in the i386 supported hardware list.  I'd expect the other
boards in the dc-300 series to work as well since they all
make the same claims of compatibility.  One cool feature
of these boards is that they support disk mirroring in the
firmware--neato.

    DC-300B: ISA
    DC-320E: EISA
    DC-380: VLB
    DC-390: PCI

 - todd