Komputerbay 4GB DDR2 533MHz PC2-4200 PC2-4300 DDR2 533 (240 PIN) DIMM Desktop Memory 4GB DDR2 533MHz PC2-4200 PC2-4300 DDR2 533 (240 PIN) DIMM Desktop Memory 100% Compatible with Desktops. BRAND NEW 4GB PC2-4200 PC2-4300 DDR2 533 Mhz. Supports Dual Channel. Compatible with DESKTOPS THAT SUPPORT DDR2 240PIN MEMORY Lifetime Warranty