4GB Memory Upgrade for MSI Motherboard FM2-A55M-E33 DDR3 P3-12800 1600MHz NON-ECC Desktop DIMM RAM Upgrade (PARTS-QUICK BRAND) Capacity: 4GB Form Factor: 240 pin DIMM Speed: PC3-12800 DDR3 1600MHz Halogen Free; ROHS; Warranty: Lifetime