4GB 2X2GB RAM Memory for Dell OptiPlex 780 (Performance Mini Tower ) DDR3 DIMM 240pin PC3-8500 1066MHz Black Diamond Memory Module Upgrade - Walmart.com
8GB Kit (2 X 4GB) DDR3 Memory Upgrade for Dell OptiPlex 780 Small Form Factor Desktop PC PC3-12800 240 pin 1600MHz RAM (PARTS-QUICK Brand) at Amazon.com
Dell Optiplex 780 Upgrade RAM | Anthony's Studio
Dell Optiplex 780 Upgrade Video Card RAM SSD Power Supply - YouTube
2GB Memory Upgrade for Dell Optiplex 780 DT/MT/SFF DDR3 PC3-10600 1333MHz DIMM Non-ECC Desktop RAM (PARTS-QUICK Brand) at Amazon.com
2GB RAM Memory for Dell OptiPlex 780 (Performance Mini Tower ) 240pin PC3-8500 DDR3 DIMM 1066MHz Black Diamond Memory Module Upgrade - Walmart.com
Dell Optiplex 780 Upgrade Options - Dell Community
Dell Optiplex 780 Small Form Factor Desktop for Work & School - Eco Computer Co.