Kuesuny 8GB Kit (2 x 4GB) DDR3-1600 SODIMM, DDR3L PC3-12800 CL11 Non ECC Unbuffered 204-Pin 1.35V/1.5V 2RX8 SO-DIMM Notebook Laptop RAM Memory at Amazon.com
Amazon.com: SK Hynix 4GB 2RX8 PC3-12800E 1600MHZ HMT351U7CFR8C-PB 00D4957 00D4955 47J0180 Compatible with IBM System x3100 M4 IBM System x3250 M4 : Electronics