O2 is an entry-level workstation running OC Unix , introduced in 1996 by Silicon Graphics (SGI) as a replacement for their earlier Indy series of workstations. Like Indy, O2 used the same processor with the MIPS architecture and was intended for use primarily for multimedia. His more powerful fellow was SGI Octane . In 2002, O2 was replaced by a series of Fuel workstations.
Content
Hardware
System Architecture
O2 has a proprietary high-bandwidth Unified Memory Architecture (UMA) that connects various system components. The system has a UMA- PCI bridge, one PCI slot is available to the user. O2 has an elegant body and modular internal design. Inside, there is space for two SCSI disks that are mounted on special skids (in later models based on the R10000 / R12000, due to restrictions associated with the cooling system, only one disk was left space) and an additional video / audio capture cassette installed with left side on the back of the case. Additional information on the O2 device can be obtained from the SGI documentation. Also, detailed diagrams of the internal device can be found here .
CPU
There are two varieties of O2 that differ in the central processors: the cheaper version with MIPS R5000 / RM5200 / RM7000 processors operating at frequencies of 180-350 MHz, and the more expensive one with R10000 / R12000 processors with frequencies from 150 to 400 MHz. R5000 200MHz CPUs with 1MB L2 cache are typically noticeably faster than 180MHz processors with 512K Cache. There is an amateur project, within the framework of which a MIPS RM7000 processor (PMC-Sierra RM7000C-600T) with a frequency of 600 MHz was installed in O2.
On the motherboard of all O2 models, there are 8 DIMM slots, and the memory can be expanded up to 1 GB. O2 is equipped with an UltraWide SCSI-based disk subsystem. Older O2 models typically had 4-speed Toshiba CD-ROM drives, but any SCSI CD-ROM and many SCSI CD-RW drives can be used instead, but Audio-CD can only be played with Toshiba drives. O2 + models came with Toshiba SCSI DVD-ROM. Models with R5000 / RM5200 / RM7000 processors have two SCA UltraWide SCSI hard drive bays. Since models with R10000 / R12000 processors have significantly larger cooling fans, there is only room for one hard drive bay in these models. Work in a local area network is provided by the built-in 10/100 Base-T Ethernet adapter.
Graphics Subsystem
- The CRM chipset developed by SGI for O2 distributes OpenGL computing between the central processor and the graphics chip. Due to the use of a unified memory architecture, the frame buffer is located in the main memory of the system, and the amount of memory under the texture is limited only by the physical amount of system memory.
- Graphics accelerator ICE.
- OpenGL 1.1 + extensions for ARB images.
Operating System
- IRIX 6.3 or 6.5.x (native platform for O2)
- Linux is ported and works only on R5000 and RM5200 processors, some drivers are missing. Gentoo and Debian distributions have released versions that run on O2. For more information, see the IP32 port page on linux-mips.org.
- OpenBSD has supported O2 (R5000 / RM5200 / RM7000) since OpenBSD version 3.7. See the sgi page.
- NetBSD has supported O2 (R5000 / RM5200 / R10000 / R12000) since NetBSD 2.0. See the sgimips page.
Performance
O2 has built-in hardware for processing streaming media and still images, called ICE (Image Compression Engine - or Image Compression Engine). ICE consists of two parts: a 64-bit control device based on R4000 operating at a frequency of 66 MHz and a 128-bit central processor with SIMD architecture operating at a frequency of 66 MHz. This device only supports integer arithmetic, but nevertheless provides a significant amount of computing power, which allows O2 to perform video and audio encoding tasks that would require a significantly faster processor if solved by software. Currently, this device only works with the IRIX operating system, as it is the only system equipped with drivers that allow you to use this device.
The unified memory architecture means that O2 uses the main memory to store textures, which makes the task of texturing polygons and other graphic primitives much simpler. Instead of transferring the textures via the bus to the graphics subsystem, a pointer to the memory area occupied by the texture in the main memory is passed to O2, which is then used to access the texture of the graphics hardware. This simplifies the use of large textures, and even allows you to use streaming video as textures.
Although today the frequencies of the central processor at 180-350 MHz seem small, at the time of the release of O2 in 1996, these speeds could compete with the speeds of the then x86 family computers , and even exceeded them. In addition to this, the features listed above made O2 an excellent graphic workstation, namely, it was aimed at this market segment. However, O2 could not withstand competition with the PC market and, even taking into account the improvements that were regularly made to increase its speed, cheaper x86 computers began to overtake it in performance by the end of its release period.
Application
- Image processing (especially in the medical field)
- Live TV Graphics
- Desktop workstations
- 3D modeling
- Post-processing of analog video
- Defense complex