G.SKILL Ripjaws X Series 8GB 240-Pin SDRAM DDR3 1600 Memory - Newegg.com
G.Skill Ripjaws X Series 16 GB (2 x 8 GB) 240-Pin SDRAM (PC3-12800) DDR3 1600 CL10-10-10-30 1.50V Dual Channel Desktop Memory Model F3-12800CL10D-16GBXL at Amazon.com
HP RAM Module 1 x 4 GB DDR3 SDRAM 1333MHz DDR3-1333/PC3-10600 Registered Internal Memory 604504-B21 at Amazon.com