This O2 started as a pretty standard R5000 180MHz. That doesn't tell the whole story though, as it still has a raft of its original details--Granite keyboard, mouse, camera, and speakers, mic, cardboard boxes, printed manuals, etc. Something of a treasure trove of memorabilia. It was also my first SGI, so holds a special place.
I recently swapped out the drive for a quieter IBM with a fresh install of 6.5.22m. I also upgraded the PSU fan to a quiet Noctua. (I saved the originals in both cases.)
Because it is nearly silent and has tiny power consumption, this has become my daily-use SGI.
earlgrey:~$ hinv -vm
CPU: MIPS R5000 Processor Chip Revision: 10.0
FPU: MIPS R5000 Floating Point Coprocessor Revision: 10.0
1 300 MHZ IP32 Processor
Main memory size: 512 Mbytes
Secondary unified instruction/data cache size: 1 Mbyte on Processor 0
Instruction cache size: 32 Kbytes
Data cache size: 32 Kbytes
FLASH PROM version 4.18
Integral SCSI controller 0: Version ADAPTEC 7880
Disk drive: unit 1 on SCSI controller 0 (unit 1)
CDROM: unit 4 on SCSI controller 0
Integral SCSI controller 1: Version ADAPTEC 7880
On-board serial ports: tty1
On-board serial ports: tty2
On-board EPP/ECP parallel port
CRM graphics installed
Integral Ethernet: ec0, version 1
Iris Audio Processor: version A3 revision 0
PCI Adapter ID (vendor 0x9004, device 0x8078) PCI slot 1
PCI Adapter ID (vendor 0x9004, device 0x8078) PCI slot 2
Video: MVP unit 0 version 1.4
AV: AV1 Card version 1, Camera not connected.
1600SW Flat Panel adapter board and display.
Graphics board 0 is "CRM" graphics.
Managed (":0.0") 1600x1024
board revision 2, CRM revision C, GBE revision B
Timing table flags:
Monitor 0 type: Unknown
Origin = (0,0)
Video Output: 1600 pixels, 1024 lines, 60.00Hz (1600x1024_60p)