User`s manual

2-6
X7DCA-L User's Manual
2-3 Installing DIMMs
Note: Check the Supermicro web site for recommended memory modules.
CAUTION
Exercise extreme care when installing or removing DIMM
modules to prevent any possible damage. Also note that the
memory is interleaved to improve performance (see step 1).
DIMM Installation (See Figure 2-2)
Insert the desired number of DIMMs into the memory slots, starting with DIMM •
#1A. The memory scheme is interleaved, so you must install two modules at a
time, beginning with DIMM 1A, DIMM 1B, then DIMM 2A, DIMM 2B, and DIMM
3A, DIMM 3B.
Insert each DIMM module vertically into its slot. Pay attention to the notch along •
the bottom of the module to prevent inserting the DIMM module incorrectly.
Gently press down on the DIMM module until it snaps into place in the slot. •
Repeat for all modules (see step 1 above).
Memory Support
The X7DCA-L supports up to 48 GB Buffered (Registered) ECC DDR2 667/533
in 6 DIMMs. Populating memory slots of the same bank with a pair of memory
modules of the same size and same type will result in two-way Interleaved
Memory which will improve memory performance.
Notes:
1: Due to OS limitations, some operating systems may not show more than
4 GB of memory.
2: Due to memory allocation to system devices, memory remaining avail-
able for operational use will be reduced when 4 GB of RAM is used. The
reduction in memory availability is disproportional. (Refer to the following
Memory Availability Table for details. For Microsoft Windows users: Microsoft
implemented a design change in Windows XP with Service Pack 2 (SP2) and
Windows Vista. This change is specic to the Physical Address Extension
(PAE) mode behavior which improves driver compatibility. For more informa-
tion, please read the following article at Microsoft’s Knowledge Base website
at: http://support.microsoft.com/kb/888137.