RM Nimbus: Success breeds success

After selling what seems like the same machine since forever, or at least 1977 - the Research Machines 380Z - RM has finally stepped into the world of the IBM PC.

Except that it's not quite - it ran MS-DOS 3.1, but wasn't actually fully IBM compatible. Nevertheless, the advert suggests that "a vast range of generic MS-DOS software" ran on it.

It also one of relatively few micros that used Intel's 80186 CPU. Produced as an update to the 8086 line of chips, the 186 wasn't compatible with most of the support chips that had grown up around the more popular CPU and so most manufacturers chose to wait for the 80286 instead.

The advert mentions networking capability as a feature. Apparently, most Nimbus PC-186's were intended as workstations in a local area network setup and had no hard disks of their own[source: https://en.wikipedia.org/wiki/RM_Nimbus]. As such, they started from floppy disk or remotely over the network - very much an antecedent of the "thin client" idea that became popular in the late 90s.