[jan-jaap]

Well, regardless whether it's a quirk, a bug or simply a different interpretation of the spec that didn't play nice going forward in time -- the pin compatible WD33C93A doesn't have it.

The IBM Ultrastar 9ES (DDRS-34560) I borrowed from my 4D/440 is also from '97 or '98 and a "SCSI-3 FAST-20 SE 50-pin" device and it worked, so the IO3B doesn't disapprove all of them.

The ST118273N has a jumper to disable parity, I can see if that makes a difference. I played with the 'Force SE' jumper on some disks, that didn't change anything. Neither did (Delayed) Motor Start.

---

Regarding the Vigra VME card:

The Release notes of the VigraSound software for IRIX 5.2 or 5.3 say:

      IRIS Audio Library (AL) Execution Environment for VigraSound
      VME audio provides an audio environment for Onyx/Challenge
      systems which is binary compatible with SGI Indigo2, Indy,
      Indigo, and 4D/3X Personal Iris workstations.

      Release 1.0 supports: SGI Onyx, Challenge L, and Challenge
      XL systems running IRIX 5.3.

(Emphasis mine)

The software may install on a Crimson running 5.3, but the kernel code, usr/cpu/sysgen/IP19boot/kdsp_vigra110.o, is limited to CPUBOARD=IP19 in the .idb file so that won't install and essentially there's no driver. The versions of VigraSound for IRIX 6.x have kernel code for IP19, IP21 and IP25.

Perhaps the people in Geoman's referenced articles wrote their own code. It wasn't uncommon in those days, and with VME hardware.

About the Vigra showing (or not) in 'hinv': anything that 'hinv' knows about was hardcoded in the IRIX kernel and the 'hinv' command. It's not a dynamic system. So a 3rd party option will never show, unless it masquerades as something that IRIX already knew about.