Refurb Weekend: Silicon Graphics Indigo² IMPACT 10000 This detailed blog post documents a refurbishing project on a Silicon Graphics Indigo² IMPACT 10000 vintage workstation acquired about a decade ago. The author explores both the hardware and software refurbishing process, as well as the historical context and technology evolution of SGI MIPS systems and their CPUs. --- Background and Context The Indigo² is a powerful SGI workstation with a MIPS R10000 CPU and IMPACT graphics (Solid IMPACT version in this case). The author also owns two other SGI systems: SGI Fuel (900MHz R16000, high-end server/workstation system) SGI Indy (pizzabox form factor, older, personal favorite) The Indigo² IMPACT line evolved from the R4000-series Indigo2s (IP22 family) with increasing CPU and graphics options. The "Power Indigo²" introduced the R8000 processor family (IP26), but it was quickly superseded by the R10000 due to limitations. The R10000 (IP28) is an out-of-order execution MIPS IV CPU with advanced pipeline, branch prediction, and cache features. Graphics evolved from the Extreme (multiple cards) to IMPACT architecture, featuring advanced geometry, raster and texture engines, and different tiers (Solid IMPACT, High IMPACT, Maximum IMPACT). --- Hardware Overview & Teardown The Indigo² machine weighs over 40 pounds and features a striking purple case. Rear ports include: 13W3 video (sync-on-green) SCSI 50-pin for external storage Multiple audio jacks including IEC958 (S/PDIF) PS/2 keyboard and mouse Serial ports, parallel port, and Ethernet (10BaseT and AUI) Interior accessed by removing front bezel and top case revealing: Dual hard drive bays with custom sleds Optical drive bay (5.25") CPU board with R10000SC CPU module (195MHz) Solid IMPACT graphics card (single card, large heatsinks) RAM slots, populated with FPM 60ns parity SIMMs (upgrade potential discussed) Power supply noted as unreliable and original --- Key Discoveries and Repairs The Dallas DS1286 timekeeper chip had failed (contains battery-backed RTC, watchdog, NVRAM). The author arranged for a repair by socketing a small repair board that supports a replaceable battery. Issues with drives: Original optical drive was a Mac drive (Sony CDU948S) that did not support parity enabling, making it unbootable. Replaced with a Toshiba SD-M1711 SCSI DVD-ROM, which worked for booting the miniroot. One hard disk was improperly cabled (no SCSI ID cable), causing device conflicts. Used a ZuluSCSI replacement for the broken hard disk sled to install a solid state disk image. Graphics: Sync-on-green video output required a special monitor or an active sync converter. Machine powered and displayed PROM monitor GUI via capture box during refurb. RAM is upgraded with additional SIMMs; official limits and practical considerations detailed. Diagnostic run passed all tests including CPU, FPU, audio, SCSI, and IMPACT graphics. --- Software and Boot Process The Indigo² boots with a graphical ARCS-based PROM monitor, providing a mouse-driven interface and diagnostic menus. The standalone PROM shell supports command-line commands like hinv and boot. The initial disk image was not formatted, preventing boot. IRIX 6.5.22 (the last officially supported version for the Indigo²) is installed: Partitioning done with fx Installation done from the SCSI DVD-ROM using IRIX Tools CD sets Multiple disc swaps and set selections (default apps include Netscape 4.8a, Java 1.4, Acrobat Reader 4.05b) System configured with: Hostname: purplehaze Network initially unconfigured, then set up (static IP used) User accounts created, including root and demo Desktop environment is 4Dwm with Motif, the hallmark of SGI IRIX systems. The machine now boots cleanly with stable green power LED. --- Historical