8GB modules. Each module is: 8GB, 240 pin DIMM, DDR2 PC2-5300F, PC2-5, DDR2-667, 1024x72 Crucial Part No: Ct102472AF667 36FA1D4 Note, this is fully buffered ECC memory. These modules were removed from an HP DL 580 server that operated in a very clean controlled environment. Please verify that these MicronCrucial modules are compatible with the server motherboard you are going to use them in. See pictures to verify the module part numbers you will receive.