Hyper X 2GB 800MHz DDR2 Non-ECC CL5 (5-5-5-15) DIMM (kit of 2)...Standard 128M X 64 Non-ECC 800MHz 240-pin Unbuffered DIMM (SDRAM-DDR2, 2.0V, CL5, Gold). Kingston's KHX6400D2K2/2G is a kit of two 128M x 64-bit 1GB (1024MB) DDR2-800 CL5 SDRAM (Synchronous DRAM) memory modules, based on sixteen 64M x 8-bit DDR2 FBGA components per module. Total kit capacity is 2GB (2048MB). Each module pair has been tested to run at DDR2 800MHz at low latency timing of 5-5-5-15 at 2.0V. The SPD is programmed to JEDEC standard latency 667Mhz timing of 5-5-5-15 at 1.8V. This 240-pin DIMM uses gold contact fingers and requires +1.8V.