4GB DDR3-1333 (PC3-10600) RAM Memory Upgrade for The Dell Optiplex 790 USFF (Genuine A-Tech Brand) at Amazon.com
How To Upgrade/Replace the RAM in Dell Optiplex 790! - YouTube
Dell Optiplex 790 MINI PC USFF i5-2400 256GB SSD 16GB RAM Windows 10 Pro wifi | eBay
Restored Dell Optiplex 790 Windows 10 Pro Desktop PC Tower Core i5 3.1GHz Processor 8GB RAM 1TB Hard Drive with DVD-RW- Computer (Refurbished) - Walmart.com
Restored Dell Optiplex 790 Desktop Computer PC Intel i3-2120 3.3GHz 4GB Ram 250GB Hard Drive Windows 10 Professional (Refurbished) - Walmart.com
Amazon.com: DELL Optiplex 790 SFF Small Form Factor Business Desktop Computer PC (Intel Dual Core i3 CPU 3.3GHz, 4GB DDR3 Memory, 500GB HDD, DVDRW, Windows 10 Professional) (Renewed)'] : Electronics
Dell Optiplex 790 DT Intel Core i3-2100 3.10GHz CPU 4GB RAM No HDD No OS | eBay