MIPS Magnum

Components

Processors

The MIPS Magnum R4000 PC-50 includes a MIPS R4000PC processor with only 16 kB primary cache (but no secondary cache), running at an external clock rate of 50 Mhz (which was internally doubled in the microprocessor to 100 MHz).

The MIPS Magnum R4000 SC-50 is identical to the Magnum R4000PC, but includes one megabyte of secondary cache in addition to the primary cache.

Memory

The MIPS Magnum R4000 accepted eight 72-pin true-parity SIMMS, up to a maximum of 256 MB.

SCSI

Ethernet

Framebuffer

Serial and Parallel I/O

Floppy disk

Historical development

The MIPS Magnum 3000 used a MIPS R3000 processor and a custom, proprietary motherboard which incorporated the Turbochannel bus licensed from DEC (it is noted that DEC also manufactured the DECStation line of workstations running Ultrix, which also used MIPS processors and the Turbochannel bus). The Magnum 3000 ran only MIPS Computer Systems, Inc.'s port of UNIX System V, known as RISC/os.

The later Magnums, the MIPS Magnum R4000PC and MIPS Magnum R4000SC, also used a MIPS microprocessor — the MIPS R4000, a full 64-bit microprocessor available either in a low-cost version (the R4000PC) having 16kB of primary cache but no secondary cache, or a higher-performance version (the R4000SC) with 1MB of secondary cache in addition to the 16kB of primary cache.

As MIPS Computer Systems, Inc. had co-founded the Advanced Computing Environment consortium with Silicon Graphics, Microsoft, Motorola and others, the MIPS Magnum R4000 was intended to be MIPS' entry into the Windows NT workstation market. However, because MIPS Computer Systems, Inc.'s in-house effort to design a MIPS-based Windows NT system had met delays, MIPS Technologies abandoned its in-house efforts and instead licensed the Jazz design which Microsoft had developed in the early 1990s to facilitate the porting and development of Windows NT (it is to be noted that Windows NT was first developed on the MIPS architecture, and was only later ported to the Intel 386, DEC Alpha, and PowerPC architectures).

As such, the MIPS Magnum R4000 (and indeed all Jazz-based systems, such as the Acer PICA, NEC RISCstation, Olivetti M700, Siemens-Nixdorf RM200, etc.) incorporated many features more common to Intel-based PC's than to the commercial UNIX workstations of the era — for example, the Magnum R4000 included an EISA bus, used IBM PS/2-compatible keyboards and mice, and used commodity chipset components whose control registers were mapped to memory locations set forth in the IBM AT standard.

Operating Systems

Windows NT

The MIPS Magnum R4000 was supported by Windows NT from version 3.1 (released in 1993) through version 4.0 (released in 1996). However, support by Microsoft for all MIPS systems ended with the release of Windows NT version 4.0, and useful software for Windows/MIPS — either from Microsoft or third-party vendors — was very scarce even when MIPS was supported (for example, Microsoft never ported its own Microsoft Office suite to MIPS).

The MIPS Magnum 3000, unlike the MIPS Magnum R4000, was not able to run Windows NT.

RISC/os

NetBSD and OpenBSD

For the earlier, RISC/os-only MIPS Magnum 3000 machines, the correct port is NetBSD/mipsco. For the later, Windows NT-capable MIPS Magnum R4000, the correct port is NetBSD/arc.

Linux

Emulation

External Links