Crucial Technology CT25664AA800 2 GB 240-pin DIMM DDR2 PC2-6400 Memory Module 2 GB DIMM: 1.8V 256Meg x 64 PC Memory Technology - DDR2 SDRAM Form Factor - 240-pin DIMM Form Factor -- 240-pin DIMM Memory Speed -- 800MHz DDR2-800/PC2-6400