Specifications: 1) Type: DDRI, 333MHz-PC2700, 184PIN DDRii, 400MHz-PC3200. 184PIN 533MHz-PC4300 240PIN 667MHz-PC5300 240PIN SDRAM PC133 168PIN 2) Total memory: 256MB / 512MB / 1GB 3) Operating system compatibility: PC 4) Warranty: 3-year 5)Brand: Kingston, Hynix