RISC Technology Personal Computer.
(Commonly, but incorrectly, known as the "PC-RT", later
changed to just "RT")
IBM's first
RISC-based
Unix
computer. The RT-PC was the predecessor to IBM's
RS/6000.
It ran
AIX 1.x and 2.x and had a PC-AT bus and IBM's
ROMP
microprocessor. It was withdrawn from the marketing
around 1989 or 1990.