Updated x1
Earlier this morning, I got OpenBSD 4.6 to boot on the Octane2. It installs fine and boots from the hard-drive as well as can be expected. I get all the way to logging in and trying to ping another machine before I notice the problem.
It has no network. This is rather irritating. I shall explore further, and report my findings.
OpenBSD boron.tamber-krain.homeip.net 4.6 GENERIC-IP30#23 sgi