Well, I finally found a .pdf Owner's Manual online for the Optiplex 7040 mini-tower...mainly covers adding/replacing components. Very lacking in the specifications area.
I've been staying with Optiplex, mostly for somewhat upgraded components over consumer-tier, and ease of service. Plus, familiarity, having worked for NYS for decades, and that's all they buy.
This model made some questionable decisions, that could not be over-rided during configuration of options...a single HDMI port, no DVI outputs available, inclusion of an unidentified legacy serial port (RS232?). Plus with WIN 10, some of my hardware lacks drivers, like my big-bucks slide/negative scanner, but at least a 3rd-party is offering a driver for $45. Once set-up, I'll try compatibility mode, or whatever it is now called in WIN 10...
I'm expecting a steep learning-curve...I was an XP "power-user" before retiring 4 years ago, when NYS hadn't yet even migrated to WIN 7, due to being almost bankrupt, a big deal when there are hundreds of thousands of desktops on one network, including licenses, installs, and user re-training costs. I ordered both the Win 10 "For Dummies" and "Missing Manual" books, to avoid taking a class. "Missing Manual" seems to assume competence with WIN 7/8, which I lack.
Don't presume dinosaurs are extinct...I'm living proof.