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
8GB DDR3 Memory for Dell Optiplex 3040 Mini Tower PC3L-12800 Desktop DIMM RAM (MemoryMasters) at Amazon.com