Windows XP on a Dell Optiplex 3040 SFF : r/techsupport
Dell Optiplex 3040 Micro Intel i5-6500T 2.50GHz CPU 4GB RAM No HDD No
Amazon.com: Dell Optiplex 3040 Micro Computer Mini Tower PC Intel Quad Core i5-6500T, 8GB DDR4 RAM, 256GB SSD, Win 10 Pro (Renewed) : Electronics
Amazon.com: Dell OptiPlex 3040 Small Form Factor PC, Intel Quad Core i5 6500 up to 3.6GHz, 16G DDR3L, 256GB SSD, WiFi, Windows 10 Pro 64-English/Spanish/French(Renewed) : Electronics
Refurbished: Dell OptiPlex 3040, Minitower, Intel Core i5-6500 @ 3.20 GHz, 8GB DDR3, NEW 1TB SSD, DVD-RW, Microsoft Windows 10 Home 64-bit - Newegg.com
Dell Optiplex 3040 SFF i3-6100 3.70GHz 4GB RAM No HDD No OS