2GB Kit (1GB x 2) XMS2-6400 (800MHz Xtreme Performance Memory) DDR2 240-pin DIMM Non-ECC Unbuffered Latency 5-5-5-18 at 1.9V 64Mx8 matched pair...This is a 2GByte kit two-rank DDR2 SDRAM DIMM designed for extreme speed. This part delivers outstanding performance in the latest generation of DDR2-based motherboards. It has been tested extensively in multiple DDR2 motherboards to ensure compatibility and performance at its rated speed. This memory has been verified to operate at 800MHz at the low latencies of 5-5-5-18.