User Guide

Hardware Installation
2-24
For double side memory module, there is one limitation. This mainboard supports
only 4 RAS# (Row address latch) signals for DRAM control. They can only be
occupied by one DRAM module, they can not be shared. The simple rule is: If
double side module at either Bank0 or DIMM1, the other must be empty. If
you use at DIMM1, Bank0 must be empty. Bank1 and DIMM2 have the same
limitation.
Double side module at either Bank0 or
DIMM1, the other must be empty.
Double side module at either Bank1 or
DIMM2, the other must be empty.
Following table explains more about the RAS limitation. You can see that Bank0
1st side and DIMM1 2nd side use the same RAS0#, and Bank0 2nd side and
DIMM1 1st side use the same RAS1#. If you are using single side SIMM at
Bank0 and single side DIMM at DIMM1, it should be no problem. But only one
double side DIMM or double side SIMM can be at Bank0 or DIMM1.
Bank0
1st
side
Bank0
2nd
side
Bank1
1st
side
Bank1
2nd
side
DIMM1
1st
side
DIMM1
2nd
side
DIMM2
1st
side
DIMM2
2nd
side
RAS0#
X X
RAS1#
X X
RAS2#
X X
RAS3#
X X
Caution: Make sure that you install the same SIMM type
and size for each bank.
Caution: There are some old DIMMs made by EDO or
FPM memory chip, they can only accept 5V power and
probably can not fit into the DIMM socket, make sure
you have 3.3V true SDRAM DIMM before your insert it.