IIRC, Tandy Computers was sold off to AST, which Radio Shack continued to stock, so in a way Tandy computers lasted a good bit longer than the Tandy Computer label itself did.
Back in the 90's, I worked for a Tandy owned consumer electronics business called AV&C (which stood for, unimaginatively, Audio, Video, & Computers). This store chain was very small, operating out of the southeast region. It was spun off of the McDuff chain which Tandy acquired. Most of the employees I worked with were long-time McDuff's employees, which I believe either worked there before Tandy acquired them or slightly after. McDuff was actually a pretty nice store located in our local mall (and quite a few others), a more high-end type store that sold a wider variety of computers and TVs than Radio Shack did. One of the former managers told me about how Tandy closed up their shop. He showed up to work one morning to open the store and there was a corporate person there, with a big semi truck around the back of the building to load up the entire store! He had no idea they were closing the store until he showed up to work. They then offered everyone that worked there a job in "nearby" store and if they didn't take the deal they were given their severance package.
When AV&C came along, we had a much bigger expanded showroom (where a Rex store was once occupied), selling lots and lots of different brand of computers (arguably too many) and a lot of . A lot of the computer offerings competed directly with Radio Shack, which seemed pretty dumb. Even dumber was that we were allowed to see the transfer/warehouse cost of each item sold in the store. To our surprise the Radio Shack transfer costs were almost always cheaper for the same items, even though they came from the same physical warehouse. At the time I worked here, we had a lot of competition not only from Radio Shack, but also the likes of Office Depot, Campo, Circuit City (if they were from out of town), and Sears. There were a lot of players in the field then.
Most of the software we sold was barely competitively priced, and languished on the shelves for a long time. In that segment there was even more competition, and most if not all the players got their software (including us) from Ingram Micro. I think they more than anyone has #@$@#ed the software reseller business. That distribution model favors the absolute largest retailers (since they will get the deepest discounts). No mom and pop retailer can make money reselling Ingram Micro goods IMO. But I digress.
Anyways, back to the issue at hand. It was clear before I quit that the writing was on the wall for ol' AV&C, so I bailed and found work elsewhere. A few months later the Tandy closed all the remaining stores. They weren't the only ones either. I think about the same time Tandy also closed the Incredible Universe stores (or a good chunk of them) and Campo went out of business completely. That pretty much left CompUSA, Best Buy, and Circuit City. Hmmm, seems oddly familiar to the current situation: lousy market, too many players...I wonder if they'll survive now. Best Buy's having problems competing with online retailers, I can't imagine how Radio Shack can fare since every Tom, Dick, and Harry sells phones and satellite dish setups now.
I also remember the awesome catalogues Tandy had, as well as their (quite expensive but undeniably well made) house brand stuff. I think I have a working Realistic 27MHz CB radio somewhere at my parents house ...!!