Apple Power Macintosh 4400 - Manual (Page 156)

You can increase your computer’s DRAM to a maximum of 160 MB by
having an Apple-authorized dealer or service provider remove the preinstalled
DRAM DIMM if necessary, then install a 32 MB DIMM in slot 1, and two
64 MB DIMMs in slots 2 and 3. DIMMs of mixed sizes may be installed one
at a time in any order in the memory slots—for example, you can install one
8 MB DIMM and one 16 MB DIMM.
Note: Slot 1 is labeled “single bank” and can only accept single bank
DIMMs. Slots 2 and 3 are labeled “dual bank” and can accept either single
bank or dual bank DIMMs—the DIMM manufacturer can tell you what kind
of DIMM you have.
IMPORTANT The DIMMs should be 64-bit wide, 168-pin 3.3-volt (V)
unbuffered Extended Data Output (EDO) DRAM DIMMs, with
60-nanosecond (ns) RAM access time or faster, and a 1K or 2K refresh
count. The DIMMS must be composed of DRAM chips with a row and
column configuration of 10 by 10, 11 by 10, 11 by 11, or 12 by 9. The 64-bit
wide, 168-pin, 5-V buffered fast-page or EDO DRAM DIMMs from other
Macintosh computers are not compatible with your computer and should not
be used. Do not use DIMMs that support a 4K refresh count.
The DRAM sockets are located behind the card that supports the PCI cards
in your computer. It may be difficult to maneuver the DRAM DIMMs in this
space, so Apple recommends that you have an Apple-authorized service
provider install your DRAM DIMMs.
Video DIMM configurations
Increasing your computer’s video memory can result in faster video
performance. Your computer’s video memory can be increased to a maximum
of 4 MB. You can use the following types and sizes of video DIMMs in
your computer:
m +5-V EDO DRAM—1 MB or 2 MB sizes
m +3.3-V SGRAM—2 MB or 4 MB sizes
156 Appendix B