[callahan]

Hmm. All that looks right compared to my stock Octane. 

Any chance there is a physical problem with your disk? 

Also, I've never used fx in auto mode, I always manually tell it r/ro and create/sync labels.

Another thing I've heard folklore of is that Irix can fail to load doing a basic reformat presumably because of old blocks that aren't overwritten. The solution there is to use fx's exercise tool in write mode. I can't personally vouch for that being an issue, however.