In Figure 4, you can see the four memory sockets this motherboard has. According to the manufacturer, EP45-UD3L is compatible with DDR2 memory up to 1366 MHz or more, due to its thicker copper tracks.

Like all other Intel-based socket 775 motherboards, this board is able to access memory in dual channel channel configuration. In order to enable this feature, simply install two (or four) identical modules, in pairs, in the sockets with same color. Intel P45 chipset supports up to 16 GB of DDR2 memory, and so this motherboard. This chipset also supports DDR3 memory modules, but the EP45-UD3L has no sockets for this type of memory.

 
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Figure 4: Memory Sockets.