The Curious Case of the Unix workstation layout

Summary

The Curious Case of the UNIX workstation layout Posted on 2025-07-19 Contents Background Cathode Ray Dude recently did an excellent video about the history of the PC case, particularly the early- and mid-1990s, and the various mainboard layouts that pre-date the ATX standard. You should watch it. Here it is. VIDEO The rest of this blog will contain some spoilers for that video. UNIX workstations I have a bunch of 1990's RISC/UNIX workstations. I don't really know how it happened, but I went from having literally none back in October 2024, to having: Silicon Graphics Power Indigo² Sun Ultra 80 HP 9000 Visualize B132L+ HP 9000 Visualize C3000 HP 9000 712 (running NeXTSTEP!) Apple PowerMac 7200/90 (ok, Mac OS 7.6 Is Not UNIX, but I could install Linux or NetBSD if I wanted to) I also briefly had an Alphastation 500, but I failed to get it working so I passed it on to someone who knows much more about them than me. And watching CRD's video. I realised something. Silicon Graphics The Silicon Graphics IRIS Indigo is a tower workstation of the old-school. A light make-over of the previous IRIS 4D series, it has two huge PCBs, which insert vertical into a backplane using rotating clips. I'm pretty sure it's actually a VME bus design, both because of that Wikipedia page but because SGI Depot describes them as part of the "IRIS VME Series". (ctvoigt, CC BY-SA 3.0 DE https://creativecommons.org/licenses/by-sa/3.0/de/deed.en, via Wikimedia Commons) But the Indigo² that came after it? Desktop case. Flat mainboard with ports on the rear. PSU on the right. Card riser on the left, with cards on the left. It takes standard PC SIMMs, and has PS/2 connectors for the keyboard and mouse. By jove it looks like LPX. Eh, maybe it's a one-off. HP 9000 I have wanted a PA-RISC machine for a while, but now I find myself owning three. The HP 9000 series has a long and storied history, and you should just go and read http://openpa.net because it is an excellent resource. My new HP 7000 712 is th...