Lot of 6 Kingston 4GB ECC Unbuffered RAM 1Rx8 PC3-12800E+2Rx8 PC3-10600E-Tested | eBay
Beware of the single rank x16 RAM kits sneaked in some laptop models! The 1Rx16 modules have significantly lower bandwidth compared to the 1Rx8 variants - NotebookCheck.net News