SGI Indy
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Overview
The Indy was the fruit of SGI's effort to muscle into the market for desktop publishing, low-end CAD, and multimedia. At the time, the market was mostly dominated by Apple. The Indy was the first computer to include a digital video camera, and was built with a forward-looking architecture including an on-board ISDN adapter. With the inclusion of analog and digital I/O, SCSI, and standard composite and S-Video inputs, the Indy really was a multimedia machine.
At the beginning of its life, the Indy came standard with 16MB of RAM. IRIX 5.1, the first OS for the Indy, did not take full advantage of the hardware due to inadequate memory management. SGI realized this and quickly increased the base specification to 32 MB, at considerable cost. Subsequent IRIX releases made huge improvements in memory usage.
Physical characteristics
The Indy packed a reasonable amount of power into a very small (41 cm × 36 cm × 8 cm), simple, and elegant package. The sturdy, pastel-colored "pizza box" chassis is comparable to a small desktop PC from the same era, and is designed to fit underneath a large CRT monitor.
One option for the Indy was a floptical drive. The floptical used 21 MB disks, but was also able to read and write standard magnetic floppies as well.
Processors
Early Indys used the 100MHz MIPS R4000 CPU, which quickly proved inadequate. So the Indy, at the bottom of SGI's price list, became the primary platform for MIPS's low-cost, low-power-consumption R4600 CPU series. The R4600 had impressive integer performance, but had poor floating-point capability. This, however, wasn't too huge of a problem in a box that was generally not designed for FP-intensive applications. And the R4400 was an option, anyway. For this reason, the R4600 made an appearance outside the Indy line just once, and only briefly, in the SGI Indigo2.
R4600s both with an L2 cache (SC) and without (PC) are common in the Indy. At the same clock rate, the SC version of the chip is generally 20 to 40 percent faster than the PC version, due to the memory cache.
The Indy was also the first SGI to utilize the MIPS R5000 CPU, which offered significant advantages over the R4400 and R4600 it replaced. The Indy's 180MHz R5000 module can be overclocked to 200MHz by replacing its crystal oscillator chip.
Graphics
Three graphics subsystems were available for the Indy: 8-bit XL, 24-bit XL, and 24-bit XZ. Each supported a resolution of 1280 × 1024 at a refresh rate of 76 Hz, and had a Sun-style 13W3 monitor connection.
8-bit XL
Also known as Newport graphics, these were designed for general 2D X11 applications; no hardware 3D acceleration was included. These worked best for 2D CAD or general office use.
24-bit XL (XGE)
Identical to the 8-bit XL in every way except color depth. A popular choice for some general graphics work, since its 2D performance is better than the XZ card.
In an R5000 Indy, these graphics are called XGE, because an R5000 CPU had better 3D performance than the XZ subsystem's two GEs - therefore, all 3D is done in software, faster than hardware XZ. XZ graphics were never paired with the R5000 for this reason.
XZ
These graphics were a port of the Indigo2's XZ (Elan) graphics into Indy - they offered very good non-textured 3D performance at the time, sacrificing a bit of 2D performance in return. In R5000 Indys, they were sacked in favor of software 3D, because software 3D on an R5000 is faster. These graphics take the form of two boards, one on top of the other, and occupy one GIO slot.
Video
The Indy was the first SGI to have video inputs by default. Each and every Indy has a composite, S-Video, and digital video input built into the motherboard, which collectively are known as "Vino" video. None of them are of professional quality, but are still usable. The digital input is a proprietary D-sub connector with a rectangular array of pins, and is used by the SGI IndyCam. The connector is the same as serial ports on Cisco routers, however is electrically different.
The maximum supported input resolution is 640x480 (NTSC) or 768x576 (PAL). It takes a fast machine to capture at either of these resolutions, though; if you have, say, a meager 133MHz R4600PC CPU, you're going to have to lower the input resolution. However, if all you want to do is display the video on the screen without capturing to disk, the Vino hardware is capable of DMAing directly into video memory with only trivial CPU overhead.
None of the Indys support a video output by default - that would require the Indy Video GIO32 card. On top of that, there is an optional module called CosmoCompress, which offers on-the-fly JPEG video compression and decompression and uses up another GIO32 slot.
Drives
The Indy has two drive bays for 1-inch tall 3.5" drives. The upper drive bay is externally accessible and may hold a SCSI floptical drive. All external and internal drives share a single Fast SCSI bus (unless a GIO32 SCSI card has been installed).
Networking
All Indys shipped with AUI/10BASE-T Ethernet and ISDN as standard equipment. The Ethernet ports are half-duplex only, use is mutually exclusive. The 10BaseT port takes precedence over the AUI port - if the system detects a carrier on both ports, it will use the 10Base-T.
A 100BASE-TX Ethernet card GIO32 was available through the manufacturer Phobos.
The ISDN port has no NT1. You will need to pick up an external NT1 if you wish to use an ISDN network connection in North America.
Continued use
The component of the Indy most prone to failure is the Nidec/Power General power supply. New power supplies are manufactured by Sony and sold through resellers, however they are expensive.
The Indy's Ethernet address, which doubles as the system's serial number, is stored in battery-backed RAM. This means that when the internal battery dies, so does the system - it will hang at the PROM montior and refuse to boot any further as a result of the Ethernet address being all FFs. A non-amateur user can replace the PROM battery and reprogramme it, but the replacement battery is not manufactured anymore.
(Originally based upon Alex's SGI page (http://www.tc.umn.edu/~dols0011/sgi/), public domain as of September 7 2003)
External links
- Extensive information about the Indy: Reputable Systems (http://www.reputable.com/indytech.html)