Various 4 GB RAM DDR 3 modules for laptop SAMSUNG model M471B5273CH0-CK0 (1 module) HYNIX model HMT351S6CFFR8C-H9 (6 modules) KINGSTON model X7C75G -HYC S0196Q (2 modules) FREE with any purchase above : 1 pair of 2GB DDR3 - PC3 10600s SAMSUNG model M471B577CDH0 - CH9