Acer Altos G5450 Series - Manual (Page 70)

3 System upgrade 52
Upgrading the system memory
This section includes instructions for removing and installing a DIMM
(dual in-line memory module).
Altos G5450 has sixteen DIMM slots. Each CPU controls eight DIMM
slots. The DIMM slots support dual channel DDR2 -667 registered ECC
memory modules.
Important: When you are using a single-processor server, you
should install a pair of identical modules into the DIMM A1 and
B1, DIMM A2 and B2, DIMM A3 and B3, DIMM A4 and B4 slots.
The DIMM C1 to DIMM D4 slots are enabled when a second CPU is
installed on the mainboard. For instructions on how to install an
additional CPU, see “To install a second processor:” on page 51.
When you are using a dual-processor server, you should employ a
paired DIMM configuration by installing modules in the DIMM A,B
and DIMM C,D slots.