> So far the only really 'stable' RC is RC2.

You're just getting lucky.  There is a known design "feature" with the
R10k when implemented in non-coherent I/O platforms (like the IP32) that
makes it prone to reboot during I/O.  Executive summary is that all DMA
buffers should be mapped into KSEG2 above 8MB; the current code doesn't
do that.

(reference http://mail-index.netbsd.org/port-sgimips/2000/06/29/0006.html)

-- Chris