Samsung ram Memory 4GB (1 x 4GB) DDR3 PC3-12800,1600MHz, 204 PIN, SODIMM for laptops at Amazon.com
HP 4 GB DDR3 SDRAM Memory Module - 4 GB (1 x 4 GB) - 1333MHz DDR3-1333/PC3-10600 - DDR3 SDRAM - 240-pin DIMM at Amazon.com
Addon-Memory 1 x 4GB DDR3 SDRAM DIMM 240-Pin AM160D3SR4EN/4G at Amazon.com
VGP-MM4GBD-AX RAM Module - 4 GB (1 x 4 GB) - DDR3 SDRAM at Amazon.com
OWC 8 GB (2 X 4GB) ram PC8500 DDR3 1066MHz sodimm 204-pin Memory Upgrade Kit, (OWC8566DDR3S8GP), Compatible with MacBook Pro, MacBook, Mac Mini and iMac at Amazon.com
8GB (2 X 4GB) DDR3 1600MHz PC3-12800 240-pin Memory RAM DIMM Kit for Desktop PC by NEMIX RAM at Amazon.com