Kingston ValueRAM 4 GB Kit (2x2 GB Modules) 1333MHz PC3-1066 DDR3 DIMM Desktop Memory KVR1333D3N9K2/4G Two 2GB modules, totaling 4GBStandard 256M X 64 Non-ECC 1333MHz 240-pin Unbuffered DIMM (DDR3, 1.5V, CL9, FBGA, Gold)