The Quadra 605 (and its twins, the
LC 475 and Performa 475/476) has 4 MB of RAM soldered to the
motherboard and a single 72-pin SIMM socket for memory
With the rear of the computer away
from you, you will see a SIMM socket just behind the fan,
running from the front of the computer to the rear. This can
be filled with a 1 MB, 2 MB, 4 MB, 8 MB, 16 MB, 32 MB, 64 MB
or 128 MB SIMM. The 72-pin SIMM must be 80ns or faster.
(Apple has not certified the 605 with 64 MB or 128 MB SIMMs,
since they were introduced after the computer. Field reports
indicate they work.)
To add memory, simply put the new
SIMM in the RAM socket.
The Quadra 605 ships with 512 KB
VRAM, two 256 KB VRAM SIMMs. You can upgrade this to 1 MB by
replacing the 256 KB VRAM SIMMs with 512 KB VRAM