DDR2 DIMM sockets supporting up to 4 GB of system memory
Dual channel memory architecture
Support for DDR2 1066/800/667 MHz memory modules
Because of chipset limitations
*To avoid the system being unable to start or the memory being incorrectly detected, if only one memory module is to be installed, we suggest that you install it on the DDR2_1 or DDR2_3 socket.
*To install two memory modules, we suggest that you install them on the DDR2_1 and DDR2_3 sockets, when the DDR2_2 or DDR2_4 socket is populated with a DDR2 1066 MHz memory module, the memory speed will be downgraded to 800 MHz).
*when using FSB 1333 MHz CPU with populating all DIMM sockets, memory frequency will be reduced from the original, and system instability or incorrect detection of memory module may be occur.
(Please refer "Memory Support List" for memory support information) GIGABYTE - Motherboard - Socket 775 - GA-EP31-DS3L (rev. 2.1)