MemoryTek 4GB (2x 2GB) DDR2 PC2-6300 PC2-6400 800Mhz 240 Pin DIMM (Desktop Memory) 4 GB KIT Lifetime Warranty. Seller pays return shipping if anything is wrong Well Tested. Unique design with shorter height Non ECC and Non Parity Memory Speed: 800 MHz. Supports Dual Channel 4GB 2x 2GB DDR2 PC2 6400 800MHz 240 Pin DIMM 4 GB KIT