MSI K7N2 User Guide - Page 28

Hardware Setup Memory The mainboard provides 3 slots for 184-pin DDR SDRAM DIMM (Double In-Line Memory Module) modules and supports the memory size up to 3GB. You can install DDR200/266/333/400 modules on the DDR DIMM slots (DIMM 1~3). Please note that the system supports 128-bit dual channel DDR when you install DDR modules on DIMM1 (purple slot) and DIMM3 (green slot), or DIMM2 (purple slot) and DIMM3 (green slot). DDR DIMM Slots (DDR 1~3) Introduction to DDR SDRAM DDR (Double Data Rate) SDRAM is similar to conventional SDRAM, but doubles the rate by transferring data twice per cycle. It uses 2.5 volts as opposed to 3.3 volts used in SDR SDRAM, and requires 184-pin DIMM modules rather than 168-pin DIMM modules used by SDR SDRAM. High memory bandwidth makes DDR an ideal solution for high performance PC, workstations and servers. 2-7