Memory RAM Upgrade for Dell Optiplex 790 Desktop 4GB/8GB DDR3 DIMM

4GB DDR3 PC3-10600 1333MHz 240-pin DIMM. 8GB DDR3 PC3-10600 1333MHz 240-pin DIMM. You can install different sized modules together in your machine. For example: Installing 2 x 8GB alongside 2 x 4GB will be 100% compatible.

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