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Dell Optiplex 3020 SFF Computer PC, Intel Core i3-4130 3.4Ghz, 8GB RAM, 500GB SATA HDD, DVD Windows 10, includes 19" LCD, keyboard, and mouse, 1 year warranty - Walmart.com
Dell Optiplex 3020 Upgrade RAM, Video Card, Hard Drive Install Change Replace - YouTube
How to Install Memory in a Dell OptiPlex 3020 Computer - YouTube