755 in a 780 optiplex

[1240east]

can i use ram from a 755 dell optiplex in a 780 optiplex

 

[The Paladin]

Dell OptiPlex 755 manual Specifications https://www.manualslib.com/manual/356816/Dell-Optiplex-755.html?page=97#manual
Dell OptiPlex 780 manual Specifications https://www.manualslib.com/manual/227530/Dell-Optiplex-780-Usff.html?page=9#manual

Short Version answer; No

Because
Dell OptiPlex 755 uses DDR2 667-MHz or 800-MHz
Dell OptiPlex 780 Uses DDR3 1066MHz and 1333MHz