AOpen MX6E PLUS Manual page 32

Hardware Installation
III. Buffered and non-buffered: This motherboard supports non-buffered
DIMMs. You can identify non-buffered DIMMs and buffered DIMMs
according to the position of the notch, following figure is for your reference:
non-buffered
Reserved
buffered
Because the positions are different, only non-buffered DIMMs can be
inserted into the DIMM sockets on this motherboard. Although most of
DIMMs on current market are non-buffered, we still recommend you to ask
your dealer for the correct type.
IV. 2-clock and 4-clock signals: Although both of 2-clock and 4-clock signals
are supported by AX6LC Lite, we strongly recommend you to choose 4-
clock SDRAM in consideration of reliability.
Tip: To identify 2-clock and 4-clock SDRAM, you
may check if there are traces connected to golden
finger pin 79 and pin 163 of the SDRAM. If there
are traces, the SDRAM is probably 4-clock;
Otherwise, it is 2-clock.
V. Parity: This motherboard supports standard 64 bit wide (without parity) and
72-bit wide (with parity) DIMM modules.
There is no jumper setting required for the memory size or type. It is
automatically detected by the system BIOS, and the total memory size is to add
them together. The maximum is 256MB.
EX chipset only supports 3V EDO or SDRAM, so we can mix EDO and SDRAM
without any problem.
Every DIMM socket can be EDO or SDRAM. Please note that the maximum
DRAM size of DIMM1 is 128MB, but DIMM2 plus DIMM3 can only be
128MB.
Total Memory Size = Size of DIMM1 + Size of DIMM2 + Size of DIMM3
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