500670-B21-AM - 4Gb, 400MHz, DDR2-400/PC2-3200, 240-pin

AddOn Networks 4GB DDR2-400. Internal memory: 4 GB, Memory layout (modules x size): 2 x 2 GB, Internal memory type: DDR2, Memory clock speed: 400 MHz, Memory form factor: 240-pin DIMM, ECC

These parts are FACTORY ORIGINAL Tier 1 modules (from either Samsung, Micron, Hynix, Infineon, etc.). You cannot buy a better module, and there is a good chance that it is an identical module you may get directly from the OEM. All ACP modules are built to meet or exceed OEM specifications, and JEDEC standards. All memory modules come with a Lifetime warranty and are 100% guaranteed compatible for the appropriate systems it is intended for.