The Silicon Graphics (SGI) O2 is a MIPS-based single CPU entry-level Unix workstation. Introduced in 1996 as a multimedia workstation, the O2 was a worthy successor to the successful Indy workstation.
Hardware
System architecture
The O2 features a proprietary high-bandwidth Unified Memory Architecture (UMA) that connects the various system components. A PCI bus is bridged unto the UMA. Designer case and totally modular construction.
CPU
The O2 comes in two distinct CPU flavours; the low-end MIPS 180-300Mhz R5000/R7000 based units and the higher-end 175-400Mhz R10000/R12000 based units. The 200Mhz R5000 CPU's with 1Mb L2-cache are generally noticeably faster than than the 180Mhz R5000's with only 512Kb cache. There is a hobbist project that has successfully retrofitted a 600Mhz R7xxx MIPS processor into the O2.
There are 8 DIMM slots on the motherboard and memory on all O2's is expandable to 1Gb. The O2 carries an UltraWide SCSI drive subsystem. Older O2 generally have 4x speed Toshiba CD-ROMs, but any Toshiba SCSI CD-ROM will fit. The R5000/R7000 units have two available drive sleds for SCA UltraWide SCSI hard-disks. Due to the fact that the R10000/R12000 CPU module has a much higher cooling-fan assembly, the R10000/R12000 units have room for only one drive-sled. Networking is provided through an integrated 10 Base-T ethernet port.
Graphics
The CRM chipset that SGI developed for the O2, shares OpenGL calculations between CPU and chip. Framebuffer memory comes from main memory - 'Unlimited' Texture memory.
ICE accellerator
OpenGL 1.1 + ARB image extensions.
OS
IRIX 6.3 or 6.5.x
Linux port has some functionality
OpenBSD is supported as well
Performance
hardware MJPEG compression, massive textures. Slow CPU, most software not optimised for O2 platform.
Use
(Medical) Imaging, on-air TV graphics, Desktop workstation, 3D modelling, Analogue video post-production, Defense industries
Folklore
User-friendly
The see-through skins
PeeCee mods
