Epson 4000 - Manual (Page 115)

Controller Problems
You see a
controller error
for
the
hard
disk drive controller
or the I/O
port
controllers when you start your system.
The indicated controller on your system board may be faulty.
If you have an option card with a controller that will work with
your device, you can install it and change the jumper settings
on the system board to disable the built-in controller. You can
then continue to use your system until it is convenient for you
to have it serviced.
External Cache Problems
The
cache
displayed by the power-on
diagnostics
program
is incorrect.
You may have installed the external cache chips incorrectly.
They may be the wrong type, or they may not be inserted all
the way.
Also, you may not have changed the SETUP program or the
jumpers to recognize the new cache. Make sure you have set
the External cache option to Enabled and set both the
System shadow and the Video shadow options to
Enabled.
See Chapter 4 for instructions on changing the jumper settings
or information on installing external cache; see Chapter 2 for
instructions on using the SETUP program.
Troubleshooting 7-13