Kingston Value (KVR16N11S8/4) RAM 4GB 1600MHz PC3-12800 DDR3 Non-ECC CL11 DIMM SR x8 Desktop Memory at Amazon.com
CMS 4GB (2X2GB) DDR3 10600 1333MHZ NON ECC DIMM Memory Ram Upgrade Compatible with HP/Compaq® Compaq 8100 Elite Small Form Factor Business Pc - A79 - Walmart.com
4GB Memory Upgrade for MacBook Pro, iMac, and Mac mini