8GB 4X2GB Dell OptiPlex 755 Series Desktop/PC DDR2 PC2-5300 RAM Memory at Amazon.com
Dell OptiPlex 755 Tower Core 2 Duo 3 GHz - HDD 1 TB RAM 4GB | Back Market
2 GB Dell New Certified Memory RAM Upgrade for Dell OptiPlex 755 & 760 Systems SNPYG410C/2G A2149880 : Amazon.com.au: Computers
Refurbished Dell OptiPlex 755 Tower Desktop PC with Intel Core 2 Duo Processor, 4GB Memory, 250GB Hard Drive and Windows 10 Pro (Monitor Not Included) - Walmart.com
Used Dell Optiplex 755 Tower Intel Core 2 Duo 3.0Ghz Processor, 4GB RAM, 1TB Hard Drive, DVD-Rom, Windows 10 Home 64 Bit - Walmart.com