HELP: Upgrade 3.5 to 4.1

[elroy]

I just decided to bite the figurative bullet and upgrade my 3/50 from 3.5
to SunOS 4.1.  Problem is, the 4.1 install won't boot off the tape.  I've
got a 3/50 monochrome with a Toshiba 140mb disk and 60mb tape (standard
shoebox), and a Parity 4mb memory board.  I drop to the prom and do a:

    b st()install sd(0,0,1)

and get back:

    invalid page bus error:
    Vaddr: FEFE0038, Paddr: 00000038, Type 0, Read FC5, Size 4

Sun, of course, wants me to yank out the Parity board before they'll look
at it (and I don't blame them for that).  However, that's a day of
downtime.  Has anybody else out there on the net run into this, or have
any suggestions?  I'd like to avoid tearing open the system if I can.
Thanks.

Mark Anacker				...!dsinet!marka -or- ...!toybox!msa
Digital Systems International, Inc.	Redmond, WA   USA    (206) 881-7544