Data General was a pioneering firm in the minicomputer world, known primarily for their Nova 16-bit minicomputer which gained a wide following and was used in many forms for over a decade. A series of mis-steps and bad releases almost killed the company in the 1980s, but they continued as a shell of their former greatness into the 1990s, eventually being bought out in 1999.
Data General formed when, in traditional computing style, several engineers from local companies got fed up with management and left to form their own company. In this case the main protagonists were Edson De Castro and Henry Burrkardt III of DEC, and Herbert Richman of Fairchild Semiconductor.
De Castro was the chief engineer on the PDP-8, DEC's line of inexpensive computers that created the minicomputer concept. It was designed specifically to be used in lab equipment settings, and as the technology improved was able to be shrunk to fit into a 19-inch rack, where many still operate today, decades later. de Castro was convinced he could do one better, and started work on his new 16-bit design.
The result was released in 1969 as the Nova. Like the later PDP-8 machines, it was a rackmount machine, but smaller in height and considerably faster. Launching it as the best small computer in the world the Nova quickly gained a huge following and made the company cash flush. The original Nova was then quickly followed by the faster SuperNova, and then by a slew of minor versions based on the SuperNova core. The last major version, the Nova 4, was released in 1978, once again the only Nova for sale. During this period the Nova generated 20% annual growth rates for the company, which became a star in the business community.
The Nova had been supplanted in 1974 by their upscale 16-bit machine, the Eclipse. It was based on many of the same concepts as the Nova, but included support for virtual memory and multitasking more suitable to the small office than the lab. It was also packaged differently for this reason, in a floor-standing case the size of a small fridge. Production problems with the Eclipse led to a rash of lawsuits in the late 1970s, after new versions of the machine were pre-ordered by many DG customers, and then never arrived. After over a year of this many decided to sue, while others simply left. It appeared that the Eclipse was originally intended to replace the Nova outright, and the Nova 3 series released at the same time was phased out the next year. However, strong continuing demand resulted in the Nova 4. The Nova 4 might also be a result of the continuing problems with the Eclipse.
In 1976 DEC announced the VAX series, their first 32-bit minicomputers, which they described as super-minis. The first products would not be released for a few years, but that would be just when current 16-bit machines would be getting old enough to replace. DG immediately launched their own 32-bit effort in 1976 to build the world's best 32-bit machine, known as the Fountainhead Project. However when the VAX 11/780 was released in 1978, Fountainhead was nowhere near ready to deliver a machine, largely due to problems in project management. DG's customers quickly started leaving for the VAX world.
Data General then launched a crash 32-bit effort based on the Eclipse, known as the Eagle Project. By late 1979 it became clear that Eagle would deliver before Fountainhead, and an intense turf war started inside the company for the ever-shrinking budgets. Meanwhile customers were abandoning DG in droves, driven both by the delivery problems with the original Eclipse, as well as the power of the new VAX. The project was written on in depth in Tracy Kidder's Pulitzer prize-winning book, The Soul of a New Machine, making the MV line the best documented computer project in history, at least from a human perspective.
In two short years the first results of the project were released in 1980, the Eclipse MV/8000. While technically competent, the MV was too little, too late. While it kept them alive with good sales in 83 and 84, many of DG's customers had already moved to the VAX platform and wouldn't be buying new machines for at least a couple of years. At the same time the microcomputer was rapidly making inroads to the lower-end market, and the introduction of the first workstations wiped out all 16-bit lab machines, once DG's best customer segment. While the MV series did stop the erosion of DG's customer base, this now smaller base was no longer large enough to allow DG to develop their next generation, when they needed to. DG exited the propietary hardware business completely in 1988, killing the MV in the process.
They then tried again, this time with Unix-based machines instead of those based on their own operating systems. The result was a technically interesting series of Unix servers known as the AViiON line, combined with large disk systems known as CLARiiON. Their strategy change to being the first to use the commodity hardware in a data-processing suitable machine. In this they appear to have been only marginally successful, and after betting their AViiON line on the Motorola 88000 they found that the true commodity processor, the Intel 8088, was quickly running away from them in performance in the early 1990s. They then moved to Intel based machines, but the customers were long gone by this point. CLARiiON did better, and its sales were still strong enough in 1999 to make DG a takeover target, and they were bought out by EMC, a major data storage company.
Today all that is left of Data General is their web page at http://www.dg.com, which doesn't even mention the company name.