option card — the G364 framebuffer. The G364 includes a SUN 13W3-style output (which can be converted to the more common VGA pin-out), and is capable of pixel screen resolutions of 640x480, 800x600, 1024x768, or 1280x1024. Because it is a simple framebuffer, the G364 does not include any accelerated graphics functions. Serial and Parallel I/O The MIPS Magnum R4000 also includes two standard RS-232-capable serial ports and an IBM AT-compatible parallel port. Floppy disk Also, the MIPS Magnum R4000 had an IBM AT-compatible floppy disk controller and a single floppy drive bay. Historical development The MIPS Magnum 3000 used a MIPS R3000 processor and a custom, proprietary motherboard which incorporated the TURBOchannel bus (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 RISC/os, which was MIPS Computer Systems, Inc.'s proprietary port of BSD Unix including some System V features. 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 16 kB of L1 cache but no L2 cache, or a higher-performance version (the R4000SC) with 1 MB of secondary cache in addition to the 16 kB 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 was first developed on the MIPS architecture, and was only later ported to the Intel 386, 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, 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