(1) An early series of RISC-based, 32-bit computers from Digital that ran under ULTRIX. Introduced in 1989, the 5400 model was a Q-bus system, but the 5800 model used the XMI bus.
(2) A series of mainframes from Digital that were introduced from 1974 through 1980 and were the successor to the 36-bit PDP-10 computers.
