Datasheet
2-6
X7DBU/X7DGU 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)
1. 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, then DIMM #2A and so on. (*See the
Memory Installation Table Below.)
2. 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.
3. 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 X7DBU/X7DGU supports up to 32 GB fully buffered (FBD) ECC DDR2 667/533
in 8 DIMMs. Populating DIMM modules with pairs of memory modules of the
same size and same type will result in Interleaved Memory which will increase
memory performance.
*Note 1: Due to OS limitations, some operating systems may not show more than
4 GB of memory.
*Note 2: Due to memory allocation to system devices, memory remaining available
for operational use will be reduced when 4 GB of RAM is used. The reduction in
memory availability is disproportional. (Refer to the Memory Availability Table on
the next page for details.)
Optimized DIMM Population Configurations
Branch 0 Branch 1
Number of
DIMMs
Bank 1
(Channel 0)
Bank 2
(Channel 1)
Bank 3
(Channel 2)
Bank 4
(Channel 3)
2 DIMMs 1A --- 2A --- --- --- --- ---
4 DIMMs 1A --- 2A --- 3A --- 4A ---
6 DIMMs 1A 1B 2A 2B 3A --- 4A ---
8 DIMMs 1A 1B 2A 2B 3A 3B 4A 4B
(*Notes: i. DIMM slot# specified: DIMM slot to be populated; “--
-“: DIMM slot not to be populated. ii. Both FBD 533 MHz and
667MHz DIMMs are supported; however, you need to use the
memory modules of the same speed and of the same type on a
motherboard. iii. Interleaved memory is supported when pairs
of DIMM modules are installed. For best performance, please
install memory modules in both Branch 0 and Branch 1. iv. For
memory to work properly, you need to follow the restrictions
listed above. )