parts-quick 2GB Compatible Memory for Dell Optiplex 780 DT/MT/SFF DDR3 PC3-10600 1333MHz DIMM Non-ECC Desktop RAM at Amazon.com
Restored Dell Optiplex 780-D WA1-0303 Desktop PC with Intel Core 2 Duo Processor, 4GB Memory, 320GB Hard Drive and Windows 10 Home (Monitor Not Included) (Refurbished) - Walmart.com
Dell OptiPlex 780 SFF Pentium E5800 3.20GHz CPU 4GB RAM No HDD No OS