A Moogle  🏳️‍🌈 💻 🎮 🎶 🇸🇪

Strange, the last Indigo 2 I had was a mauve type colour.

1/ The Indigo 2 line involved a bizarre, incestuous lineage of multiple distinctly different machines, all under the "Indigo 2" moniker. Let's talk about that.

2/ The first entries in the Indigo 2 line came in teal cases. They used some variant of the MIPS R4x00 architecture, and supported largely the same graphics boards as the Indy line: (2D-accelerated) 24-bit XL, (3D-accelerated) XZ, and (even faster-accelerated) Elan.

3/ This was no coincidence, as the initial line of Indigo 2 machines were, broadly, the same underlying architecture as the lower-profile and lower-cost Indy machines: The fundamental differences involved an internal optical drive bay, a second SCSI controller, and an EISA bus.

4/ As an aside, the EISA bus occupied the same segment of the machine's memory map as the Video-In No-Out ("VINO") chip on the Indy, which is fundamentally why the Indigo 2 line lacked such capabilities without a dedicated capture card.

5/ SGI started experimenting with the next generation of MIPS chips beyond the R5000, and they hit upon the R8000: A multi-chip solution with phenomenal floating-point performance. They released this as the "POWER Indigo 2" line. Same teal case, but a different CPU.

6/ This line did not last long, however. Educational institutions, in particular, quickly found that the POWER series of MIPS processors had some really gnarly floating-point bugs despite the performance. This can be confirmed by looking up contemporary posts on Usenet.

7/ Lastly, once SGI finally found a workable 64-bit architecture in the MIPS R10000 series, they released the "Indigo 2 IMPACT" line, in its notably different purple/mauve-themed case. It supported a much different line of graphics cards, to boot.