HP 512MB 133MHz SDRAM, 0.5 GB, 2 x 0.25 GB, 133 MHz, 168-pin DIMM HP 512MB 133MHz SDRAM. Component for: PC/server, Internal memory: 0.5 GB, Memory layout (modules x size): 2 x 0.25 GB, Memory clock speed: 133 MHz, Memory form factor: 168-pin DIMM, ECC