<OK, supposing I get that lot  to work, how do you tell it to boot from
<the first RX50?, I'm new to this.  The main thing I can tell you is tha

Well if you have more than 2 hard disks the rx50 is not connected!

The RQDX3 controller can have 4 drives (rx50=2!).  

<the indicator lights only come on for the top two drives when power is
<applied.  That's the HALT/READY buttons for the hard drives.  The machi
<is made up of the original machine and bits from a dead machine.

assuming there are two hard and rx50:

>>>Boot DUAn   lower case letter "n" is the physical drive number.

For two RD5Xs dua0, dua1
rx50(1) dua2
rx50(2) dua3


Allison