Memory; Introduction To Ddr2 Sdram; Memory Module Population Rules - MSI 945GM2-FR User Manual

The 945GM2 series provides 4 slots for 240-pin DDR2 DIMM, which supports
the memory size up to 4GB. And the 945PLM2 series provides 2 slots for 240-pin
DDR2 DIMM, which supports the memory size up to 2GB.
Since DDR2 modules are not interchangeable with DDR1 and the DDR2 stand-
ard is not backward compatible, you should always install DDR2 memory module in
the DDR2 slot. Otherwise, you are not able to boot up your system and your mainboard
might be damaged.
For the updated supporting memory modules, please visit http://www.msi.
com.tw/program/products/mainboard/mbd/pro_mbd_trp_list.php.

Introduction to DDR2 SDRAM

DDR2 is a new technology of memory module, and its speed is the top limit of
current DDR1 technology. DDR2 uses a 1.8V supply for core and I/O voltage, com-
pared to 2.5V for DDR1, and requires 28% less power than DDR1 chips. DDR2 truly
is the future of memory, but will require some changes as the technology is not
backwardly compatible and only motherboards specifically designed for DDR2 memory
will be able to support these chips.
DDR2 incorporates new features at the chip level that give it better signal
integrity, thereby enabling higher clock speeds.
DDR2 modules have 240 pins, versus 184 pins on a DDR1 module, and the
length of DDR2 module is 5.25". DDR2 modules have smaller and tighter spaced pins.
The height of DDR2 modules varies, but they will typically be less than 1.3" in height.

Memory Module Population Rules

Install at least one DIMM module on the slots. Each DIMM slot supports up to a
maximum size of 1GB. Users can install either single- or double-sided modules to
meet their own needs. Please note that each DIM M can work respectively for
single-channel DDR, while both channels (in different color) populated
with same amount of memory size will work as dual-channel DDR.

Memory

DIMM1~DIMM4
(from left (Orange) to right(Green))
Channel A (DIMM1 & DIMM2): Orange
Channel B (DIMM3 & DIMM4): Green
945GM2 provides 4 (DIMM1/2/3/4) slots
945PLM2 provides 2 (DIMM1/3) slots
Hardware Setup
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