System Memory; Overview - Asus M4A78 PLUS - Motherboard - ATX User Manual

3. Align the other end of the retention bracket to the retention module base. A clicking
sound denotes that the retention bracket is in place.
Ensure that the fan and heatsink assembly perfectly fits the retention mechanism module
base, otherwise you cannot snap the retention bracket in place.
4. Push down the retention bracket lock on the retention mechanism to secure the
heatsink and fan to the module base.
5. When the fan and heatsink assembly is in place, connect the CPU fan cable to the
connector on the motherboard labeled CPU_FAN.
Do not forget to connect the CPU fan connector! Hardware monitoring errors can occur if
you fail to plug this connector.
1.7

System memory

1.7.1

Overview

The motherboard comes with four Double Data Rate 2 (DDR2) Dual Inline Memory Modules
(DIMM) sockets. A DDR2 module has the same physical dimensions as a DDR DIMM but
has a 240-pin footprint compared to the 184-pin DDR DIMM. DDR2 DIMMs are notched
differently to prevent installation on a DDR DIMM socket. The figure illustrates the location of
the DDR2 DIMM sockets:
M4A78 PLUS
M4A78 PLUS 240-pin DDR2 DIMM sockets
Mode
Single-channel
Dual-channel (1)
Dual-channel (2)
1-12
DIMM_A1 DIMM_A2
- -
Populated -
Populated -
Populated Populated
Sockets
DIMM_B1
Populated
-
Populated
Populated
ASUS M4A78 PLUS
DIMM_B2
-
-
-
Populated