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Renewed Dell OptiPlex 780 SFF Desktop Intel Core 2 Duo CPU E7500 @ 2.93GHz With 90-day warranty
4 GB Dell New Certified Memory RAM Upgrade for Dell Studio XPS 8100 Desktops SNPP382HC/4G A3414608 at Amazon.com
Optiplex 780 DT, upgrading ram help - Dell Community