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SGI Octane

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SGI Octane
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The SGI Octane (and the very similar SGI Octane2) are UNIX workstations marketed by SGI. Both are SMP-capable (up to 2 identical processors) workstations, originally based on the MIPS architecture R10000 processor. Newer Octanes are based on MIPS R12000 and R14000. Octane2 has four improvements compared to Octane. Octane2 has revised power supply, system-board and xbow. Octane2 also shipped with VPro graphics and supports all available VPro cards (V6, V8, V10 and V12). Later revision Octanes also included some of the improvements mentioned. The machines shared a codename "Racer" or "Speedracer" inside SGI.

The Octane was the direct successor to the SGI Indigo2, and itself was succeeded by the SGI Tezro, and its immediate sibling is the SGI O2. SGI withdrew the Octane2 from the price book on May 26 2004, and ceased Octane2 production on June 25th, 2004. Support for the Octane2 was withdrawn in June 2009.

System Architecture

The Octane's system-board is designated as IP30. The system is based on SGI's Xtalk architecture. This means it does not use a system bus; instead it has a router XBow that connects any two of its ports. One of the ports is used for the processor and memory subsystem, one is available for PCI (actually PCI-64) expansion and four are XIO slots (packet-based high-bandwidth bus, somewhat similar to HyperTransport). This makes it very similar to a single node of the SGI Origin 200 system.

The XIO is here and there bridged to PCI-64, using a chip named BRIDGE. The places where it happens include the system board (for the IOC3 multi-I/O chip, two ISP1040B SCSI controllers and RAD1 audio), MENET cards (four IOC3s) and the PCI cage (used for PCI cards in Octane). ARCS is provided as the boot firmware, similar to all contemporary SGI computer systems.

CPU Options

SGI Part Number Description
030-0888-004 R10000 195mhz 1mb Cache
030-0890-003 DUAL R10000 200mhz 1mb Cache
030-1138-002 R10000 175mhz 1mb Cache
030-1208-002 DUAL R10000 175mhz 1mb Cache
030-1271-002 DUAL R10000 225mhz 1mb Cache
030-1272-002 R10K 225mhz 1mb Cache-NL
030-1284-002 R10000 250mhz 1mb Cache
030-1286-002 DUAL R10000 250mhz 1mb Cache
030-1355-001 R12000 300mhz 2mb Cache
030-1356-001 DUAL R12000 300mhz 2mb Cache
030-1426-001 R10000 250mhz 2mb Cache REV3
030-1427-001 DUAL R10000 250mhz 2mb Cache R3.4
030-1432-001 R12000 270mhz 2mb Cache
030-1433-001 DUAL R12000 270mhz 2mb Cache
030-1475-00x 400mhz PM10
030-1476-001 400mhz PM20
030-1590-00x 360mhz PM10
030-1591-001 360mhz PM20
030-1591-002 360mhz PM20
030-1605-001 400mhz PM10 UPGRADE
030-1605-002 400mhz PM10 UPGRADE
030-1605-003 400mhz PM10 UPGRADE

Memory Subsystem

The Octane allows 256 MB to 8 GB of system memory, using proprietary 200-pin DIMMs. There are two system board revisions. The first revision (part number 030-0887-00x, usually distinguished by a black handle) only supports 2GB of RAM while the later one (part number 030-1467-001, with a silver handle) supports up to 8GB. The -0887 revision of the mainboard will work with all 32-128 MB DIMMs and the stacked variant of 256MB DIMMs, but not the later single-board version (SGI P/N 9010036). The memory subsystem has vast reserves of bandwidth that can be directly served by the Xbow router to any XIO card.

The Octane's memory controller is aptly named HEART. It acts as a controller between the processor, the memory (SDRAM) and the XIO bus.

Graphics Subsystem

Octane Graphics Boards initially included a series of cards: SI, SI+T, SSI, MXI. These are updated XIO versions of SGI's IMPACT graphics systems that originated on the SGI Indigo2 including SGI Solid IMPACT (SI), SGI High IMPACT (SI+T) and SGI Maximum IMPACT (MXI with TRAM and SSI without TRAM). These were internally designated by SGI as 'MARDIGRAS' (MGRAS). The boards were later accelerated and re-engineered with faster geometry engine and texture modules to create new versions: SE, SE+T, SSE, EMXI (like the initial versions, the underlying EMXI and SSE boards are identical, however the EMXI includes TRAM). The SI/SE provides 13.5MB of framebuffer memory while the SSE and EMXI have a 27MB framebuffer.

SI/SSI and SE/SSE don't come with texture RAM by default. These graphics options are meant for solid modeling applications that don't need texturing. One Texture RAM module (TRAM) can be added to SI and SE graphics. Two TRAM modules can be added to SSI and SSE graphics.

  • MXI = SSI + 2 TRAM
  • MXE = SSE + 2 TRAM

The '+T' indicates an additional high speed RDRAM texture board which gives 4MB of texture memory, which is practically indispensable, though quite expensive and fragile. The SI/SE+T has one texture board while the MXI/EMXI has 2 texture boards, however, the 2 boards in the MXI/EMXI do not double the available texture memory to the system. It just doubles the texture performance.

Board Name Indigo2 IMPACT equivalent
SI+Texture High IMPACT
SSI No equivalent (Maximum IMPACT - No Texture)
SSI+Texture Maximum IMPACT (i.e. MXI)

Board Name Comments
SE E series version of SI (also known as ESI)
SE+Texture E series version of SI+Texture
SSE E series version of SSI (also known as ESSI)
SSE+Texture E series version of Maximum IMPACT
MXE E series version of Maximum IMPACT (also known as EMXI)

Later Octanes and Octane2s support the VPro graphics board series, designated 'ODYSSEY' (ODSY). The first VPro series cards were the V6 and V8. The main differentiator being that the V6 has 32MB of RAM (unlike the MARDI GRAS option, framebuffer memory and texture memory come from the same pool) and V8 having 128MB. Later, the V10 (32MB) and V12 (128MB) were introduced. The main difference with the new VPro V10/V12 series is that they had double the geometry performance of the older V6/V8. They also do not have the V6/V8_Pixel_Clock_Issues that can greatly impact usability of V6/V8 cards on some monitors. V6 and V10 can have up to 8MB RAM allocated to textures (2X more than the textured-enabled MARDIGRAS options), while V8 and V12 can have up to 108MB RAM used for textures.

The VPro graphics subsystem consists of an SGI proprietary chip set and associated software. The chip set consists of the buzz ASIC, pixel blaster and jammer (PB&J) ASIC, and associated SDRAM.

The buzz ASIC is a single-chip graphics pipeline. It operates at 251 MHz and contains on-chip SRAM. The buzz ASIC has three interfaces:

  • Host (16-bit, 400-MHz peer-to-peer XIO link)
  • SDRAM (The SDRAM is 32 MB (V6 or V10) or 128 MB (V8 or V12); the memory bus operates at half the speed of the buzz ASIC.)

As with the MARDIGRAS boards, all VPro boards support OpenGL in hardware (MARDIGRAS is OpenGL 1.1 + SGI Extensions, while VPro upgraded support to OpenGL 1.2) and OpenGL ARB imaging extensions, allowing for hardware acceleration of numerous imaging operations at real-time rates.

IMPACT Options

Option: Improved Option: GEs:
Geometry Engines
Raster Engines
Texture Modules
SI SE 1 1 none
SSI SSE 2 2 none
MXI EMXI 2 2 2

Note: Only cards with texture memory offer hardware accelerated texturing, however you can add hardware texturing to TRAMless card by adding TRAM modules to it.

VPro Options

Option: Colour: RAM: Texture Memory (up to) Geometry Speed
V6 48bit RGBA 32MB 8MB Original GE speed
V8 48bit RGBA 128MB 104MB Original GE speed
V10 48bit RGBA 32MB 8MB 2X Faster GE speed
V12 48bit RGBA 128MB 104MB 2X Faster GE speed

Compatibility: The V6/V8 boards have been shown to work with any XBow version, but the V10/V12 boards do appear to require an XBow 1.4 frontplane. The official VPro upgrade docs, including SGI's system requirements, were previously found on the SGI TechPubs site.

SI/SSI/MXI/SE/SSE/MXE graphics support the Octane Personal Video Option and the Octane Digital Video Option. The PVO or DVO won't work with VPro series graphics options. VPro series graphics require the newer DMPro video options.

More Information

More information about Octane graphics can be found on this page: Octane Graphics Boards

I/O subsystem

Octane series supports Ultra Wide SCSI devices and has two SCSI controllers. System can have up to three internal 3.5" SCSI SCA devices. Octanes use special mounting sleds for the hard drives which are compatible with SGI Origin 2000, SGI Origin 200 and SGI Onyx2. The system also has external Ultra Wide SCSI bus.


What is the HEART?

The aptly named HEART is the core of the Octane. It integrates a SDRAM memory controller, a XIO device, an interrupt controller and a processor bus interface for up to four R10000-class processors.

Access methods

The HEART can be accessed in two ways from the processor. The first one is through the PIU (Programmed I/O Unit) at 0xFF0000 in processor physical address space. The other one is at widget 8 in XIO address space. The only one way available to other XIO devices is through the widget interface, so the Interrupt Status Set register is mapped there at address 0x80.

Memory controller

The HEART contains a SDRAM memory controller with ECC. ECC errors are signaled to the CPUs by interrupts.

XIO bridge

The XIO bridge is one of the main functions of the HEART. There are three access windows defined for each XIO widget number. There is a window at 0x10000000+ W*0x1000000 for widget number W, a window at 0x800000000+W*0x80000000 and a window at 0x1000000000+W*0x1000000000.

Note that XIO accesses are deeply pipelined by default. Due to that fact, writing to any XIO widget may not have any effect for several hundred cycles. To guarantee finalization of all posted writes it is required to read the widget flush register.

The XIO bridge in HEART provides also some Flow Control features for two channels. They allow to schedule a hiwater IRQ for any given XIO register address. If the register is an input to a FIFO, as is the case with the IMPACT graphics board, exceeding a prescribed number of writes to this register would cause a FIFO hiwater condition. As you already know, the XIO writes are posted and not immediately executed. Catching the hiwater condition in the HEART and not in the card allows to trap it in a more reliable way.

Interrupt controller

The HEART interrupt controller is visible from the PIU as a set of registers: interrupt mask registers for all processors (IMR[0:3]), an interrupt status register (ISR) and ISR clear and set registers that allow atomic manipulation of the ISR.

The XIO side consists of a single register 0x80 that can accept either an atomic ISR bit set command or an atomic ISR bit clear command. These commands cause asserting and deasserting IP[7:2] bits in the CPUs whose IMRs contain the bit in question.


A small part of the HEART is a programmable interval timer, consisting of 24-bit COUNT and COMPARE registers. The IRQ can be delivered only to the IP6 bit, which is the highest-priority CPU interrupt except internal CPU timer and HEART error IRQs. The timer counts at 12.5 MHz, every 8th internal HEART cycle (1/4th of the XIO frequency).


The HEART controls also the Number In a Can associated with processor modules. It features a standard SGI issue MicroLAN controller.

Audio subsystem

Audio hardware is standard; even without extensions they can support low-latency (3 ms input-to-output) audio streams. Alesis ADAT 8-channel, 24-bit optical ports are built-in, along with S/PDIF or AES/EBU optical and coaxial ports. This makes the Octane into a respectable digital audio workstation.


The Octane uses three fans to route air throughout the system and cool key components. The largest fan, at 120mm x 38mm, is in the power supply unit (PSU). This fan pulls air through the PSU and exhausts it out the rear of the machine. In Cherokee PSUs, this fan is a Panaflo FBA12G12U. The other large fan is a 90mm x 25mm intake fan behind the SCSI cage. This fan pushes air into the machine from the rear fan opening. It also feeds vents that directly route air over the CPU. The stock intake fan is a Panaflo FBAU9A12V. Note that a 120mm fan can fit into this space, but doing so requires substantial modifications to make the fan clear the locking bar catch mechanism in addition to removing material from the plastic shroud. The final fan is a small 60mm x 10mm fan in the front of the machine that blows air over the crossbow ASIC. One version of this OEM fan is an "ICFAN" model 0610-12L.

The PSU fan operates at variable speed. You can force the fan to operate at max speed by setting the below environment variable:


The PSU fan will also operate at maximum speed if there is an XIO card in Slot C, which is the the lower-outside slot (bottom right when looking at the rear of the Octane).

Available Operating Systems

Octane and Octane 2 are both supported by OpenBSD. Both single and dual CPU configurations are supported, however at this time there is no support for running X on the IMPACT or VPro framebuffers.

Linux runs on the Octane series, although the patch is quite experimental. Link to Linux/MIPS 2.6.12 kernel patch is available in the External Links section of the page. Both graphics versions are supported, and X Window System is available on the IMPACT series.

Add-On Options

- SCSI HardDisks:

     1. SGI IBM DDRS-34560 (4GB, 7,200RPM)
        (SGI P/Ns 013-2435-001, 064-0089-001)
     2. SGI IBM DDRS-39130W S95D (9GB, 7,200RPM)
     3. IBM DRHS COMP IEC-950 (36GB, 7,200RPM)
     4. Seagate Cheetah ST336706LC (36GB, 10,000RPM)
     5. Seagate Cheetah ST173404lCV (73GB, 10,000RPM)
     6. Seagate ST373453LC (73GB, 15,000RPM)
        (Labeled "TotalStorage by IBM" IBM P/N 24P3733)


     1. ACARD AEC-7722 ATAPI/IDE device on LVD (80MB/sec) SCSI bus. 

- SCSI Cards:

- SCSI PCI Cards:

     1. QLogic QLA1240D (HVD)
     2. QLogic QLA12160 (LVD)

- Fibre Channel Cards:

- Fibre Channel PCI Cards:

     1. QLogic QLA2200

- FireWire (IEEE-1394) Cards:

- Network Cards:

- Network PCI Cards:

     1. SGI p/n 9210289 (3C996B-T-SGI1)
     2. Any Tigon3 cards should work with this hack, these include Compaq NC7770, 3Com 3c996B-T (needs the B)

- CD-ROM Drives:

- SCSI CD-ROM Drives:

     1. Toshiba TXM3401E1 (does audio cd's, but requires caddies)
     2. Plextor UltraPlex 40x

- CD-RW Drives:

- SCSI CD-RW Drives:

     1. Plextor CD-R PX-R820T 1.08
     2. Plextor Plexwriter 12/10/32
     3. Sony CRX145S 10x4x32
     4. Yamaha CRW4416SX 4x4x16
     5. Yamaha CRW6416SX 6x4x16
     6. Yamaha CRW8424SX 8x4x24
     7. Yamaha CRW2200SX 20x10x40

- DVD-ROM Drives:

- SCSI DVD-ROM Drives:

     1. Pioneer DVD-304S (bootable)
     2. Pioneer DVD-305S (bootable)


- DVD-RAM Drives:

- SCSI DVD-RAM Drives:

     1. Matshita (Panasonic) LF-D291


     1. Archive Python 4324RP


     1. Seagate CTD8000H-S (says ***octane option*** on the label)


     1. HP C1537A DDS-3 Drive

- 3.5" Floppy Drives:

     1. Teac FD-235 HS

- Removable Drives:

     1. Imation LS-120 [SCSI]
     2. Iomega Zip 100 [SCSI]
     3. Iomega Zip 100 Plus [SCSI/Parallel]

- Magneto-Optical (MO) Drives:

     1. Fujitsu MCM3064SS
     2. Fujitsu MCM3130SS
     3. Fujitsu MCJ3230SS

A detailed bilingual guide by Diego A. De Giorgio [Generatrix] can be found here: The MOD/M.O.D. (Magneto Optical Drive) IRIX FAQ

- Scanners / Printers:

     1. Epson Perfection 636 [SCSI]

- Tablets:

     1. Wacom Intuos (serial interface)
     2. Wacom Intuos2 (serial interface)

- PCMCIA Card readers:

- SCSI PCMCIA Card readers:

     1. Adtron SDDS PC Card Drive [Caveat: You need to set the speed on the SCSI ID you're using to 5MB]

- Monitors [Sync-On-Green capable]

     1. Dell 2407WFP 1920x1200_60 V8 or V12 graphics (13w3>HD15 connection)
     2. Dell 2407WFP 1920x1200_60 V12 graphics w/DCD (DVI connection)
     3. Dell P991 (works with 13w3 adapter with pins pulled)
     4. SGI GDM-20D11 (standard 13w3 connection)
     5. SGI GDM-20E21 (standard 13w3 connection)
     6. Philips 170S (13w3>HD15 connection)
     7. Dell 2007WFP 1280x1024_60 on EMXI tested only (13w3>HD15 connection)
     8. LG Flatron L1732TQ 17" 1280x1024 (13w3>HD15 connection)

Note: Monitors on the O2 Hardware Aggregator should work on the Octane as well (though a MLA will be needed with the 1600SW)

- xDSL Modem/Router combos

     1. NogaNet TENDA TED8620R (Ethernet)

Internal SCSI Drives

SGI Octane Internal SCSI Bay Caddy

All Octanes have three internal 3.5" full-height SCSI bays with industry-standard 80-pin SCA connectors. A specialized SGI caddy is required to securely mount a hard drive in the Octane. OEM caddys are sometimes offered on ebay, while 3D printed replacement designs are also available. Due to their wide availability, very fast speed, large capacities, and backwards compatibility with the Octane's Ultra Wide SCSI bus (40MB/Sec maximum), secondhand U-320 15,000 RPM SCSI drives are often recommended as replacement hard drives.

Case and Expandability

The Octane cases are large (W×H×D: 30×40×35 cm) and heavy (25 kg), yet there are no internal 5.25" drive bays, so external CD-ROM drives must be connected if desired. Extensions include video I/O, audio I/O, networking, realtime video compression boards, and external storage options (through SCSI, Fibre-Channel or FireWire). Octanes can use standard PCI cards with optional PCI cardcage aka 'shoebox' (which provides 2-full length and 1 half-length 5V PCI-64 slots), or a PCI to XIO adaptor (known as a 'shoehorn' which provides a single 3.3/5V 64-bit PCI slot).

Older Octanes can be upgraded with VPro graphics. The VPro Upgrade Installation Guide from Silicon Graphics states that V10 and V12 graphics board require an XBow revision 1.4 and Cherokee power supply. VPro V6 and V8 require a Cherokee power supply; any XBow revision will work. However, some users in the field have found that any version of VPro graphics will work with any power supply and frontplane (needs verification).

There's an easy way to (usually) identify the difference between Cherokee (747 W) and older Lucent (623 W) power supplies. The mounting handle is silver on the Cherokee International manufactured power supplies while the original Lucent manufactured ones have black handles. Unfortunately, the handles can become damaged and are very easy to replace, not necessarily with the original color. Caveat emptor.

Single-CPU Octanes and Octane2's can be upgraded to dual-CPU models by replacing the complete CPU module. Again, the official statements are that certain mainboards are required for certain CPU modules but this doesn't appear to generally hold up in the real world. Perhaps the SGI stated requirements came from early revisions of the relevant parts but no one in the hobbyist or reseller communities has yet reported a case where the official requirements were accurate.

Octane skins come in three types. The original Octane has green skins with the original 'cube' logo. The later model Octanes have skins the same colour as the original but with Octane2-style lettering and logos. Octane2 systems have blue skins with the current 'sgi' logo.

Parts compatibility between Octane and Octane2

Octane2 consists of different revisions of the Octane components, specifically a higher-wattage power supply, XBow revision 1.4 in the frontplane, and an updated IP30 (part number 030-1467-XXX) The updated IP30 allows the use of higher-density memory modules (up to 8GB total RAM). The single-board 256MB DIMMs will not work in the older 030-0887-XXX mainboards, neither will the 512MB modules or any 1GB module.


LED Lightbar

Octanes came from the factory with two ways to illuminate the lightbar mounted in the front of their case - a red LED to indicate a fault, and a pair of small incandescent lightbulbs for normal operation. However these lightbulbs will eventually fail. A popular remedy is to replace them with different colored LEDs rather than using another bulb. There is a youtube video of a lightbar disassembly and modification here.

When viewed from the top/front of the lightbar, as in the photo below (and as it would be installed in the machine), +5V common is the leftmost pin., with the rightmost pin the ground for the normal operation (white) lights. In the photo below a 68 Ohm resistor has been placed between +5V common and the positive (long) leg of two blue LEDs. The negative (short) LED legs are attached to the two ground pins of the former incandescent lights. There is no requirement for there to be a light in both locations.

LED Lightbar modification


Front plane LEDs

The LEDs are simply link status lights. There is actually seven LEDs:

BaseIO X
    QA X X PCI Expansion
    QD X X QB
    QC X X Heart

The BaseIO and Heart are connected internally and are part of the IP30, so these will always be lit. The QA-QD refer to the quad module, which is labeled like this when facing the rear of the Octane:


QA should always be lit as the first graphics card is installed in Quadrant A. The other LEDs will be lit depending on what XIO options are installed.

The PCI Expansion LED will be lit if there is a PCI shoebox installed.

Dallas NVRAM

The Octane and Octane2 use the Dallas DS1687-5 for a real-time clock function and a few hundred bytes of battery-backed RAM.

Number In a Can (NIC) Replacement

Apparently the Number In a Can, or NIC, which stores the system serial number in many SGI workstations, can go bad and require replacement. On a single CPU module for the Octane this is a surface mounted 6-pin IC designated DS2505. It is possible to swap in the NIC from another module.

Octane crashing/instability

I'm having some issues with my Octane. It's an [email protected]/512mb/SSE machine, and it doesn't seem to be able to stay up more than 2 weeks. When it crashes, it typically goes without provocation (sometimes I'll happen to be using it, sometimes it goes at night), the whole machine freezes (can't ping it externally). The display always freezes the same way, the current image on the screen holds indefinetely irregardless of peripheral input, but the colors look like film negatives of what they are supposed to be.

Reports and recommendations from usenet:

It may be a bad IP30 board version -003 which must be replaced by an IP30 board with a higher version number (-005) or by a new design of that board (part 030-1467-001 or later). Report the version number of the board you have (for instance, IP30 board, barcode HHL594, part 030-0887-004 rev C). The version number is shown on the IP30 board but can also be read under IRIX by 'hinv -mv'. Look for a line similar to:

    Location: /hw/node/xtalk/15
    IP30 Board: barcode HHL594     part 030-0887-003 rev  C

If it is IP30 board 030-0887-003 or -004, remove the power cord, ground yourself, remove the system module, put it on a flat surface with the components facing you, and press the module with the black heat sink in the center of the board firmly against the surface. Reassemble and restart the machine.

This succeeded in 10 of 10 cases with 10 different Octanes I know of. However, in some other cases the defect showed-up again after some time.

I removed the system boards and reseated the memory, cleaned the dust off the connections and it booted up right away. In some cases reseating the system module did the trick. May be it is necessary to repeat the procedure several times. However, some system modules shut-off and could not be brought back by this method.

Removed the system module and installed it into another Octane: no success, only fan and light on. Installed the system module back into the original Octane: no success, only fan and light on. Then unplugged the power cable, depressed the power button and while it was depressed I plugged the power cable in again: the machine came- up as usual.

  • Let the Octane cool down long enough and turn it on again.
  • Look for a sticking plastic power switch lever. Remove the front panel, start the machine with the chassis button, and then replace the front panel. This helped more than once.
  • Keep the air intakes clean, cooling is critical.

Try to take out the mainboard (and eventually power supply), clean it and its connectors from dust (with compressed air), put it all together and try again - we have much strange errors with Octanes that could be solved like this.

I have 0887-003 (large central black heat sink) and 0887-005 (smaller central silver heat sink) IP30s and the problems occur/have occurred with both ie. power supply fan starts when machine is connected to wall socket but nothing else happens - no LED, no response to power button. Don't know about the 0887-004 boards or the later 1467-00x boards.

Only hints I can get are that its the HEART and SPIDER chips under the central heat sink on the IP30 which cause most of the problems (see Ralf Beyer's earlier messages about pressing on the heat sink - a friend just emailed me with success by doing this but it hasn't worked on my 005 board so maybe it has something else wrong :-() and that you'll definitely get this problem if you don't keep the air intakes clean so it looks like cooling is critical too (not terribly surprising). Lastly, as mentioned earlier, it looks like transporting them doesn't help either as they seem to like being dead on arrival - I don't think I'd buy one without a warranty!

The IP30 board is 030-0887-004 Rev A. I took out the system module, placed it on a flat surface al la the instructions, pressed firmly on the central silver heat sink, reassembled the unit and bingo the Octane came straight back up. Amazing!! Initially I thought I would end up with a pretty green door stop. Thanks a lot for the help.

Enable/disable secondary CPU

In the PROM monitor, use "disable 1" to disable the second CPU. Power-cycle and reboot. IRIX will report on startup that it found 2 CPUs, but one CPU was disabled. Do the same but using "enable 1" in PROM monitor to enable the CPU.

System module stuck in chassis

As I recall, the some part of the shielding can occasionally get bent and jam the system module when it's removed roughly about 2 inches from the case.

Luckily, SGI had the foresight to include a tool to deal with this: the lockbar. Slide it into the gap between the system module and the case at whatever point feels like it's sticking, it should be just thin enough and plenty long to reach in and unhook the bent piece of shielding.

If all else fails, you should be able to remove the frontplane from the system with the system module only partly extracted. The instructions on how to do so (minus the hung-up system module) are available in the Octane Owner's Manual.

Don't forget to bend the shielding back into place when you're done extracting the system module.

There are 3 main reasons for not being able to remove an IP30 board from an Octane. They are (in order of how common):

  1. Lockbar still in place
  2. DIMM modules fallen out of the DIMM slots, lying in the bottom of the Octane chassis, keeping things from operating smoothly (hint - set the Octane on its top side and re-insert the board)
  3. The aforementioned bent metal bars on the honeycomb air filters. (hint - use the lockbar as a prybar as suggested).


  • You should never attempt to clean the compression connectors with anything other than the exact procedure described in the octane manuals. The connectors are extremely fragile and damage prone when they're apart, and can be destroyed simply by touching them, contamination with any number of things, or even by too strong a blast from a spray-duster.
The brown connectors are very sensitive compression connectors that carry data between the frontplane and the motherboard/XIO cards.

External links


Photo Gallery