Wintec Server MHzCL6 4GB(2x2GB) RegECC Kit 2Rx8 with HS 4 Dual Channel Kit DDR2 800 (PC2 6400) 240-Pin SDRAM 3RST8006R9H-4GK 240-pin Registered ECC DDR2 DIMM All contacts are gold plated Terminated command, address, and control bus Bi-directional differential data strobe Storage Capacity: 4GB