CMS 8GB (2X4GB) DDR3 10600 1333MHZ Non ECC DIMM Memory Ram Upgrade Compatible with Dell® Optiplex 390 Ddr3 Dimm - A69 at Amazon.com
Amazon.com: Dell Optiplex 390 Business High Performance SFF Desktop Computer PC (Intel Quad-Core i5-2400 up to 3.4GHz, 8GB DDR3, 1TB HDD, HDMI, DVD, Windows 10 Pro 64-bit) (Renewed) : Electronics