HP 512MB DDR-400, 0.5 GB, 1 x 0.5 GB, DDR, 400 MHz, 184-pin DIMM HP 512MB DDR-400. Component for: PC/Server, Internal memory: 0.5 GB, Memory layout (modules x size): 1 x 0.5 GB, Internal memory type: DDR, Memory clock speed: 400 MHz, Memory form factor: 184-pin DIMM