SGI O2+ Troubleshooting Guide
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Fault-finding on the SGI O2+, from the LED flow charts and diagnostics in SGI's Silicon Graphics O2+ Workstation Hardware Reference Guide (007-4486-001), with repair reports on the O2 family from the IRIXNet forum.[1] The O2+ is an O2 with more memory and disk, a newer processor and a purple case, so the community's O2 fault notes on SGI O2 Troubleshooting Guide apply to it too.[2] SGI's own procedures work down to the replaceable module: power supply, CPU module, system board, DIMMs, drives.
LED flow charts
[edit | edit source]The O2+ shows its state on a single LED on the front, beside the power button.[3] SGI's two flow charts, combined. Each ends by telling the owner to contact an SGI service provider with the system serial number to hand.[4]
| Symptom | SGI's possible causes | SGI's action |
|---|---|---|
| No LED | No power to the system; power supply failure | Check the power connections; replace the power supply |
| Solid red LED | CPU module failure | Reseat the CPU module; replace the CPU module |
| Solid amber LED | System board failure | Reseat the CPU module and the DIMMs; replace the system board |
| Blinking amber LED | Memory diagnostic failure | Check that DIMM sockets 1 and 2 are filled and reseat the DIMMs; replace the DIMMs |
| No boot tune | Volume too low; headphones plugged in; speaker failure | Turn up the volume and check for headphones; replace the system board or the chassis |
| Solid green LED | Diagnostics passed | Record any error message |
| Solid green LED, no display | Monitor off, unplugged, in power saving or turned down; cable, monitor or system board failure | Check the monitor and its connections; replace the monitor cable, monitor or system board |
| Solid green LED, keyboard prompt on screen | Keyboard not connected or faulty; system board failure | Check the keyboard connection; replace the keyboard or system board |
| Solid green LED, mouse prompt on screen | Mouse or keyboard not connected or faulty; system board failure | Check the mouse and keyboard connections; replace the mouse or system board |
| Solid green LED, no system drive | System drive not fully inserted; drive failure | Check that the drive's locking lever is pushed fully up; replace the system drive |
| Solid green LED, no CD-ROM drive | CD-ROM drive not connected or faulty | Check the CD-ROM connections; replace the CD-ROM drive |
No picture with a green LED and the boot tune
[edit | edit source]- The monitor is the likeliest cause. weblacky points out that SGI workstations, the O2 included, need a monitor that accepts sync on green, and default to 1280 × 1024; many LCD monitors from about 2005 to 2009 do. A machine that has been set to a strange resolution still shows the firmware screen briefly at power-on, so a completely blank screen points at the monitor or its adapter.[5]
- The console may have been set to the serial port, which the O2 also uses when it detects no keyboard. robespierre's fix: with the machine off, fit the jumper on J34, "FLASH Clear", near the memory banks; boot, type
resetenv(andresetpwto clear a password) at the command monitor, shut down and remove the jumper. He notes that this is documented in the O2 hardware reference manual.[5] Reading the serial console needs a null-modem cable.[5] - Passive USB-to-PS/2 adapters work only with keyboards and mice that still speak the PS/2 protocol, so a keyboard or mouse prompt with such an adapter may not mean a fault.[5]
Will not power on
[edit | edit source]- No LED at all: SGI's first steps are the power connections and then the supply.[4]
- stormy finds many O2s that do not respond to the power button, and reports that the O2 board has a "jump-start" jumper next to the NVRAM clock chip; shorting it forces the machine on.[6]
Memory
[edit | edit source]SGI's memory symptom on the O2+ is a blinking amber LED.[4] The TechPubs Wiki reports that O2 DIMMs are easily disturbed by dirt and by knocks in transit, and that careful cleaning and reseating usually cures random memory errors or a refusal to boot; it also advises checking the DIMMs for surface-mount parts knocked off by mishandling.[7] Fit DIMMs by the rules on SGI O2+ General Maintenance.
CD-ROM drive
[edit | edit source]The tray can be opened with a straightened paper clip in the hole beneath the eject button if the button does nothing.[8] On the Toshiba drives fitted to O2s, the TechPubs Wiki describes a nylon pinion on the tray motor that splits with age, so the drive cannot raise its optical block and ejects the tray as a misload; the fix is to push the gear back onto the motor shaft and glue it. The same page advises closing the tray with the inject command, not by pushing it.[7]
Handling the system module
[edit | edit source]SGI says to remove the power cable before taking out the system module.[9] weblacky goes further and removes the power supply first and refits it last whenever the system module comes out, to avoid damaging the electronics.[5]
Diagnostics
[edit | edit source]Power-on, confidence and IDE tests
[edit | edit source]The power-on tests run at every start and turn the LED red on a fault, usually with an error message. Confidence tests for the mouse, keyboard, monitor, audio and external SCSI devices are in the Toolchest under System. For the Interactive Diagnostic Environment, which takes up to 30 to 45 minutes, switch off and on, click Stop for Maintenance or press Esc, and choose Run Diagnostics (option 3); Esc stops the tests. If the System Maintenance menu cannot be reached at all, SGI treats the system as faulty.[10]
Forgotten PROM password
[edit | edit source]Switch off, remove the system module and release the PCI tray (each class has its own tray procedure). Attach the wrist strap, remove the jumper from the system board and refit it in the position shown in SGI's figure; the pin location is the same on RM7000-class and R12000-class machines. Refit the PCI tray and the system module.[11]
System crash recovery
[edit | edit source]SGI's recovery procedure starts from the reset button, pressed with a pen tip or a straightened paper clip, then Stop for Maintenance and Recover System (option 4), restoring from an IRIX CD and a backup tape.[12]
Related pages
[edit | edit source]- SGI O2+
- SGI O2+ General Maintenance
- SGI O2+ Capacitor Replacement Guide
- SGI O2 Troubleshooting Guide
- Capacitor Failure Symptoms
References
[edit | edit source]- ↑ Silicon Graphics, Silicon Graphics O2+ Workstation Hardware Reference Guide, 007-4486-001, January 2002, chapter 4 (File:SGI O2+ Workstation Hardware Reference Guide (007-4486-001).pdf).
- ↑ Silicon Graphics, Important Note: Silicon Graphics O2+ Hardware Documentation, 007-4473-001, 2001 (File:SGI O2+ Hardware Documentation Important Note (007-4473-001).pdf).
- ↑ SGI, 007-4486-001, p. 2, Figure 1-1. Front controls and LED.
- ↑ 4.0 4.1 4.2 4.3 SGI, 007-4486-001, pp. 104-105, Figures 4-1 and 4-2. Diagnostic flow charts.
- ↑ 5.0 5.1 5.2 5.3 5.4 weblacky, robespierre and jan-jaap, "O2 no boot screen, possibly in serial mode", IRIXNet forum thread 4277, May 2024, forums.irixnet.org/thread-4277.html. Sync-on-green monitors, J34 FLASH Clear jumper, resetenv, USB-to-PS/2 adapters, clock module, power supply order.
- ↑ stormy, "Octane PSU repair / Cherokee...", IRIXNet forum thread 4349, 13 October 2024, forums.irixnet.org/thread-4349.html. O2s that will not power on; the jump-start jumper.
- ↑ 7.0 7.1 "O2", TechPubs Wiki (IRIXNet community), tech-pubs.net/wiki/index.php/O2, retrieved 21 October 2026, section "Hardware Problems". Memory contacts and the CD-ROM drive pinion. Community source.
- ↑ SGI, 007-4486-001, p. 158. Opening the CD-ROM tray by hand.
- ↑ SGI, 007-4486-001, p. 28. Remove the power cable before removing the system module.
- ↑ SGI, 007-4486-001, pp. 106-107. Power-on, confidence and IDE tests.
- ↑ SGI, 007-4486-001, pp. 111-115. Disabling the system maintenance password.
- ↑ SGI, 007-4486-001, pp. 108-111. Recovering from a system crash.