Following up on my NetBSD/amd64 stability issue:

Per recommendation from Richard Rauch, I disabled ioapic and MPBIOS and
MPBIOS_SCANPCI in my kernel, and the machine has been running now for 
many hours with massive networking loads and cpu loads.

The only noticeable issue now is a periodic system hang for about 5-10
seconds on the ethernet.  This is only noticeable when running something
network-oriented (ssh, telnet, etc). Otherwise unnoticeable, and thus 
non-impactive.  No messages occur from the kernel whatsoever.  Some 
kind of timeout occurring on the network.

The machine works fine with ioapic under FreeBSD, however.

So, for my HP Pavilion a530n, ioapic and MPBIOS certainly shouldn't be
used with NetBSD/amd64.  

-scott