Abit PD5NE User Manual page 25

Installing the Mainboard
3. Maximum memory capacity 384M bytes supported by this
mainboard.
¡i
Computer
CPUs ¡j
knowledge
Pentium, Cyrix 6x86 and AMD-K5/K6 are all 64 bit CPUs, but
72-pin SIMM modules are only 32-bit. That' s why they have to
be used in pairs, because the CPU will always be only able to see
64 bits. This means that 72-pin SIMM modules have to be
installed in pairs. For instance, SIMM1 and SIMM2 must form a
pair, and
course, the two members of a pair must be of the same kind
¡i EDO or FP DRAM ¡j , and you cannot use pairs from
different "species".
But the PD5N support different "pairs" and use different type of
memory modules, notice:
After installing the DRAM, the BIOS of the mainboard will
automatically detect the size of the memory installed on the
mainboard. Below is a list of all the possible situations:
l
l
l Memory modules supported: 1Mx32 ¡i 4M ¡j , 2Mx32
Relationships between memory modules and Pentium
SIMM3 and SIMM4 must form another pair. Of
l ¡i SIMM1 and SIMM2 ¡j must use the same
memory type,
SIMM4 ¡j .
l ¡i SIMM1 and SIMM2 ¡j use the same memory
type, and ¡i SIMM3 and
the same type, or a different type, in order to permit you
to obtain the best speed configuration for each "single"
pair, and to make the system work at its maximum
capacity. If one memory pair is slower, it will have no
influence on the pair whose speed is higher.
You use 72-pin SIMM modules:
The maximum memory size is 256M bytes.
Support possible for single density or double density memory
modules.
¡i 8M ¡j , 4Mx32 ¡i 16M ¡j , 8Mx32 ¡i 32M ¡j
or 16Mx32 ¡i 64M ¡j .
¡i
as well as
SIMM4 ¡j can use
2-17
SIMM3 and