** Kingston Hyper X 4GB (2GB 256M x 64-Bit x 2 pcs.) PC2-8500 CL5 240-Pin DIMM Kit** Kingstons KHX8500D2K2/4G is a kit of two 256M x 64-bit 2GB (2048MB) DDR2-1066 CL5 SDRAM (Synchronous DRAM) memory modules, based on sixteen 128M x 8-bit DDR2 FBGA components per module. Total kit capacity is 4GB (4096MB). Each module pair has been tested to run at DDR2- 1066 M Hz at a latency timing of 5-5-5-15 at 2.2V. The SPD is programmed to JEDEC standard latency 800 Mhz timing of 5-5-5-18 at 1.8V. Each 240-pin DIMM uses gold contact fingers & requires +1.8V.