The SGI Indy

 General Information


The Indy is a nice system to start with SGI, as it is really cheap nowadays (about 100EUR).

Graphics Options

As usual there are different graphic options for the Indy available, you can chose among three different cards: 8Bit, 24Bit and XZ. The 8bit and 24bit options are based on the "newport"-architecture, whereas the XZ option is based on the "express"-architecture. The main difference is that the XZ contains a geometry processor, whereas the newport options only offer simple 2D-acceleration.

But if you have a R5000SC-180 processor, you are better off with the simple 24bit option, because the main processor is faster than the geometry processor of the XZ option. Plus 2D operations are faster on the simple 24bit graphic option.

Processor Options

The Indy supports four types of processors: The R4000, R4400, R4600 and the R5000. But beware: The R5000 will only run in an Indy with the most recent PROM version (the correct part number of the PROM is 070-9101-011). Below is a detailed table of supported processors:

Processor Speed L2 Cache Part Number
R4000PC 100 Mhz none 030-8100-002
R4000SC 100 Mhz 1MB 030-8101-004
R4400SC 100 Mhz
150 Mhz
175 Mhz
200 Mhz
1MB 030-8260-002
R4600PC 100 Mhz
133 Mhz
none 030-8236-001
R4600SC 133 Mhz 512KB 030-8252-004
R5000PC 150 Mhz none 030-0991-002
R5000SC 150 Mhz
180 Mhz
512KB 030-0986-002

Some people even succeeded in overclocking the R5000-180 processor of an Indy to run at 200MHz. Follow this link.


The Indy does not have that many graphic options as many other SGI systems - they are exactly three, no more and not less:

Name Features HW Tranformation
Entry 8bit colour no
XL24 24bit colour no
XZ 24bit colour yes
The cheapest graphic option is the Entry option (also sometimes known as XL8), and has only 8bit palettized colours, whereas XL24 supports truecolour. The XZ option also has a geometry engine and thus can offload the main processor from 3D transformations - but its 2D performance is a bit worse than the XL24. If you have a R5000 Indy, you should prefer an XL24 option to an XZ option, as the main CPU can do the transformations much faster than the graphics card, so an XZ option even slows down the graphics performance of an R5000 Indy!

The Systembus

The SGI Indy has two GIO32-bis slots on the mainboatf for extensions and for the graphics card. The GIO32-bis bus offers a bandwidth up to 100MB per second.

Since the two GIO slots on these systems are both attached to the motherboard, or CPU board, it is possible to design a board that takes up both slot spaces. GIO slots have a fixed address space. Slot 0 always occupies a particular address space while Slot 1 occupies a different address space. This is unlike VME where settings on the board itself determine the address the board responds to.


As the Indigo R4000 and the Indigo², the Indy uses standard 72pin 36bit wide PS/2 FPM memory with parity, so it should not be a big deal to find some upgrades in the second hand market. You can use SIMMs up to 32MB per module. In contrast to many PCs, you have to insert modules in groups of four and the Indy offers totally 12 slots for memory upgrades.

Power Supply

There exist two types of power suplly units (PSU) for the Indy: The first Indys had one from Nidec while the newer ones (mostly with R5000 CPU) have one from Sony. The later ones are much more silent and almost unhearable.


An Indy just needs a standard PS/2 keyboard and mouse (of course there are special gray keyboards and mice from SGI available) and has standard sound input/output connectors plus a 10MBit ethernet connector. The only item you have to care about is the monitor: Indys do have - as most SGI systems - a 13W3 monitor connector and use "sync-on-green" - although most modern PC Monitors support this method, you should assure that it really does by reading the manual before plugging it to an Indy.

Video Input and IndyCam

Probably one of the most appealing features is the video input of the Indy that is always present in contrast to all other SGI workstation from. It supports both a SVHS input plus a special connector for the famous IndyCam.

Chris Pirazzi has created a nice tty-camera application.

Video Options

  • Indy Video
    A simplified version of the Galileo video option, which still includes video input and output.
  • Video Creator
    VideoCreator is available as an optional external or internal board for video output in either compressed or uncompressed format (SCSI or VME).

My Indys

I currently own two Indys: An Indy R4600 and an Indy R5000 plus another Indy R5000.