                        EPSON AMERICA INC.
                     Product Support Bulletin

            Subject: Equity Series SIMM Compatibility

Date:  12/4/91                                    PSB No:S-0136
Page(s):  1 of 1                                  Originator:JAD

Due to the influx of third party SIMMs on the market, there are
some that are not compatible with Epson products.  This bulletin
is intended to be an aid in ensuring that only compatible SIMMs
are chosen for use in Epson's Equity Series of computers.

The SIMMs in question were SEIMENS, CUMULUS and KINGSTON.
Installing these SIMMs in Epson products may cause the
following errors:

           Parity Check 1
           18FFFE 0000 202 Memory Address Error
           164 System Options Not Set
           1500 E000 201 DOS RAM Address Error

It was thought that the chips used in these SIMMs were of poor
quality.

Epson Portland evaluated the SIMMs in question and found that
this was not true. The problem is caused by the SIMM circuit
boards (ITE and TECAP circuit boards) used to manufacture the
SIMM modules. The dimensions of these boards are not compatible
with industry standard SIMM sockets. This may result in
incomplete contact between the SIMM assembly and it's socket.
This is caused by insufficient size of the contact surfaces in
these products. Also enlarged holes in the TECAP product allow
the component pin to pass entirely through the hole without
making contact.

It is recommended that only SIMMS meeting industry standard
contact surface specifications be used in Epson Equity computer
products.

Some recommended SIMMs that were tested and found compatible
are:

           Toshiba
           Matsushita
           CDC Enterprises
           Samsung
           Aculogic

For more information contact Technical Support.
