R/S 6000: This is IBM's medium range UNIX offering. It is usually powered by at least 2 Power PC's. At work, We currently have 4 of these machines, each with 2 300MHz PPC's and 1 gig of physical memory. We run AIX on these machines. The R/S 6000 comes in many sizes, R/S 6000 is really a family designation. We have F40's at work. The F40 is the higher end R/S 6000. I have heard rummors that you can run PPC Linux on these machines. I am sure IBM has done this in their shops

Older RS/6000s were based on the POWER architecture and had MCA slots. They also had flashing lights on the front panel that gave error codes. Mine currently cycles through the uptime and load of various boxes around the network, saving me from typing.

IBM's first major entry into the "RISC" workstations market (architecture-wise), and the basis for the PowerPC CPUs currently employed in (among other things) Apple's Power Macintosh line of computers. While similar to most RISC CPU's of the day in that it used a standard load/store architecture, it doesn't have a very highly reduced instruction set, therefore calling it RISC is a bit of a misnomer (the Alpha series is similar).