Manager, systems analyst/programmer, computer graphics guhru, etc. at the CCBR/MRFIT for thirty years. Now I manage 30,000 digital images and 1,500 ancestors with a couple of Windows PCs.
The IBM 4300 series of computers were mid-range systems, various models of which were sold from 1979 through 1992. The systems, developed in Germany, were compatible with the System/370 instruction set. They featured modest electrical and cooling requirements, and thus did not require a data center environment.
Each model number was available in various sub-models, such as the 4341 model 1 (or 4341-1) and 4341 model 2 (4341-2).
The 4331 and 4341 ran the DOS/VSE operating system with FBA DASD. I/O used virtual addresses, unlike the System/370 architecture.
4300 systems were also capable of running the VM and MVS operating systems.
The 4381-13 through 4381-24 (announced in 1987) were entry-level machines for the 370/XA architecture. They were positioned between the IBM 9370 and IBM 3090 in performance at the time of announcement.