CMS 16GB (4x4GB) DDR3 10600 1333MHZ Non ECC DIMM Memory Ram Upgrade Compatible with Dell® Optiplex 980 DDR3 DIMM - C58 at Amazon.com
Dell Optiplex 980 Desktop Computer I5-660 3.3GHz 16GB 500GB Windows 10 Pro WiFi
Dell Optiplex 980 Small Form Factor Desktop w/ Intel Core i5 650@3.20GHz, 4GB DDR3 RAM, 250GB HDD and licensed Windows 7 Professional from a Microsoft Authorized Refurbisher : Amazon.ca: Electronics