Article 166834 of comp.os.vms:
        Hi, Everyone -

        I got the answer to the firmware problem!  It turns out that there
is a known incompatibility between Firmware version 3.8 (PALcode 5.56) and
oVMS 6.1 graphics drivers on the DEC3000.  DECwindows will come up properly
after upgrading the OS, or as I preferred you can just install the graphics
driver from the oVMS 6.2 Binaries CD (in this example, mounted as DKA0:).
It works now, at least for me.

$ set def SYS$COMMON:[SYS$LDR]
$ rename SYS$GXADRIVER.EXE *.OLD
$ copy DKA0:[VMS$COMMON.SYS$LDR]SYS$GXADRIVER.EXE []

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 /  | , , , , , ,_                               Gwyn F. Fireman
(__/|/(_(_)(_/|/| |_/                            Computer Sciences Corporation
   /|        /|   Gwyn.Fireman@gsfc.nasa.gov     IUE Observatory
  (_/       (_/                                  (301) 794-1560