MSI Keeper 945GM V1.0 - Manual (Page 19)

M S-9641 M ainboard
2-6
The mainboard provides 2 slots for 240-pin DDRII DIMM, which supports the
memorysize up to 2GB.Since DDRII modules are not interchangeable with DDR1 and
the DDRII standard is not backward compatible, you should always install DDRII
memory module in the DDRII slot (DIMM0~DIMM1). Otherwise, you are not able to boot
up your system and your mainboard might be damaged.
DIM M1
DIM M0
Memory
Introduction to DDRII SDRAM
DDRII is a new technology of memory module, and its speed is the top limit of
current DDR1 technology. DDRII 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. DDRII truly
is the future of memory, but will require some changes as the technology is not
backwardly compatible and only motherboards specifically designed for DDRII memory
will be able to support these chips.
DDRII incorporates new features at the chip level that give it better signal
integrity, thereby enabling higher clock speeds.
DDRII modules have 240 pins, versus 184 pins on a DDR1 module, and the
length of DDRII module is 5.25 ”. DDRII modules have smaller and tighter spaced pins.
The height of DDRII modules varies, but they will typically be less than 1.3 ” in height.
DIMM Module Combination
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 DDRII, but there are some rules while using dual-channel
DDRII. Users may install memory modules of different type and density on different-
channel DDR DIMMs. However, the same size, type and density memory modules
are necessary while using dual-channel DDR, or instability may happen. Please refer
to the following table for detailed dual-channel DDR. Other combination not listed
below will function as single-channel DDR.