<It probably means that your RD54 is dying.  (No surprise there!)
<It's possible that a reformat would help eek a few more months of life
<out of it.

Could also be that the formatting was messed up early on or the RQDX 
controller is ailing and even bad cabling.  I've seen those.  One of my 
older ones was a pull back in '89 for that symptom.  Formatted it with the 
controller it's used with and it still running.

<>Can a BA123 handle three RD54s, a TK50, and an RX50?

Yes.  I've filled all of the drive slots in the past.  It also depends on 
whats in the backplane as they pull against the same supplies.

OH, MAKE SURE ALL THREE {3} FANS are working. The powersupply fan in the 
bottom rear is often missed and can cause eratic operation and shutdowns.


Allison