User`s guide

InstaIling External Cache
Your computer comes with 256KB of external cache installed
on eight 28-pin, 32K x 8, 20ns SRAM DIP chips and one
32K x 8, 20ns tag chip. You can increase the cache to lMB by
replacing these chips with eight 128K x 8, 20ns SRAM chips.
You must install chips in one of the configurations in the table
below (each bank contains four cache memory sockets).
Cache memry configurations
BANK 0 BANK 1 Tag SRAM
U5, 6,7,8 U9,10,11,12 U50 Total cache
32K X 8 32K X 8 32K X 8 256KB
128K x 8 128K x 8
32K X 8 1MB
Follow these steps to install the external cache chips:
1. Remove the internal drive mounting bracket in your
computer. See page 5-2 for instructions.
2. Locate the external cache memory sockets on the main
system board, shown on page 4-6.
3. You may need to remove any option cards that are blocking
access to the sockets. See page 4-18 for instructions.
Caution
To avoid generating static electricity and damaging the
cache chips, ground yourself by touching the metal
surface on the inside of the computer’s back panel. Then
rem ain as stationary as possible while you install them.
4-20 Installing and Removing Options