SGI: Hardware

Octane scsi error during diagnostic

I bought a couple octane systems, all of the ones I played with so far would power on, pass diagnostic and show the prom screen with the various system options with no scsi drives attached internally or externally.
One of them however, will not pass the power on diagnostic. I gives me an error that says "Internal SCSI device/cable diagnostic failed - External SCSI device/cable diagnostic failed Check or replace "Disc, Floppy, CDROM or SCSI cable."
This is when i have no SCSI devices plugged in at all. If i connect a hard drive in the internal pay, or plug in an external CDROM, it passes the diagnostic and sends me to the prom screen just fine. hinv shows the scsi device as it should, and im able to do a ls on the device and see its contents. Is there actually a problem with the scsi on this system? I havent tried installing an operating system yet as i dont have a spare hd to put in it yet, but from what i can see via the prom it looks like its working when a drive is connected. Is there some prom setting causing this error? Also I should note, this system when i got it had the PCI card cage installed with 2 SCSI controllers installed. I removed this, so they are no longer in the system, however i get the same error with or with out the card cage/cards installed so Im not sure if this has something to do with this or not.