This lengthy reference book published by DCS was first introduced in 1991 but continued to be updated and sold throughout much of the 1990s. It provides a variety of useful information on upgrading the popular Tandy 1000 series computers. The company's 1997 catalog listed "Upgrading Your Tandy" for $19.95 USD.

The third edition contains 226 pages, including the index in the back. There are chapters on memory, hard drives, floppy drives, CD-ROM drives, modems, sound, video, expansion slots, CPUs & motherboards, ports, math co-processors, mice, keyboards, clock chips, operating systems, removing the housings, and obtaining more information.

"Upgrading Your Tandy" includes labeled diagrams of the motherboards of almost all of the 1000-series models. The first and second editions might (?) not contain information on the TL/3, RLX, or RSX models, but the third edition does. Most of the book is text, but there are occasional drawings and diagrams. The front and back covers are dark blue.