IBM 6150 RT

The IBM RT (or IBM 6150 series) was a computer workstation sold by IBM and built around IBM's ROMP processor, a spin-off of the IBM 801 pioneered at IBM Research. The system was introduced in 1986 as the RT PC (RISC Technology Personal Computer) and ran AIX 1.x and 2.x, the Academic Operating System (AOS), or the Pick operating system. It was commonly, but incorrectly, known as the PC RT, and IBM later simplified the name. It didn't enjoy much success, and all models were discontinued by May 1991. However, the system spurred further development, as it was followed by IBM's RS/6000 and the corresponding POWER processor line, which was the basis for the PowerPC.

Three models were produced, the 6150, 6151, and 6152. The basic types of machines were the tower model (6150), and the desktop model (6151). All these models featured a special board slot for the processor card, as well as machine specific RAM cards. Each machine had one processor slot, one co-processor slot, and two RAM slots.

There were three versions of the 6150/6151 processor card: the standard 032 processor card had a 5.9 MHz clock rate, 1 MB standard memory (expandable via 1 MB, 2 MB or 4 MB memory boards) and optional floating point accelerator.

The Advanced processor card had a 10 MHz clock and either 4 MB memory on the processor card, or external 4 MB ECC memory cards, and featured a built-in 20 MHz Motorola 68881 floating-point processor. The Enhanced Advanced processor card had a cycle time of 80ns, 16 MB on-board memory, while an enhanced advanced floating point accelerator was standard.

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