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4GB KIT (2 x 2GB) for Dell Optiplex 380 780 Mini Tower 780 Small Form Factor 780 XE Small Form Factor. DIMM DDR3 Non-ECC PC3-8500 1066MHz RAM Memory. Genuine A-Tech Brand. at Amazon.com
4GB DDR3 Memory Upgrade for Dell Optiplex 780 DT/MT/SFF PC3-8500 240 pin 1066MHz Desktop RAM (PARTS-QUICK Brand) at Amazon.com