DECsystem was a line of

server computer In computing, a server is a piece of computer hardware or software ( computer program) that provides functionality for other programs or devices, called " clients". This architecture is called the client–server model. Servers can provide var ...

s from

Digital Equipment Corporation Digital Equipment Corporation (DEC ), using the trademark Digital, was a major American company in the computer industry from the 1960s to the 1990s. The company was co-founded by Ken Olsen and Harlan Anderson in 1957. Olsen was president un ...

. They were based on

MIPS architecture MIPS (Microprocessor without Interlocked Pipelined Stages) is a family of reduced instruction set computer (RISC) instruction set architectures (ISA)Price, Charles (September 1995). ''MIPS IV Instruction Set'' (Revision 3.2), MIPS Technologies, ...

processors and ran DEC's version of the

UNIX Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, an ...

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also i ...

, called ULTRIX. They ranged in size from workstation-style desktop enclosures to large pedestal cabinets. The DECSYSTEM name was also used for later models of the

PDP-10 Digital Equipment Corporation (DEC)'s PDP-10, later marketed as the DECsystem-10, is a mainframe computer family manufactured beginning in 1966 and discontinued in 1983. 1970s models and beyond were marketed under the DECsystem-10 name, espec ...

, namely the DECSYSTEM-10 and

DECSYSTEM-20 The DECSYSTEM-20 was a 36-bit Digital Equipment Corporation PDP-10 mainframe computer running the TOPS-20 operating system (products introduced in 1977). PDP-10 computers running the TOPS-10 operating system were labeled ''DECsystem-10'' as a ...

series.

Models

DECsystem 3100

Identical to the DECstation 3100, but was intended to be used as a multiuser system. It was announced in early May 1989 at the UniForum exhibition in San Francisco. It was shipped in June 1989. Code name PMAX.

DECsystem 5000 Series

Rebranded Personal DECstation 5000 Series without any graphics. Code name MAXINE.

DECsystem 5000 Model 100 Series

Rebranded DECstation 5000 Model 100 Series without any graphics. Codename 3MIN.

DECsystem 5000 Model 200 Series

Rebranded DECstation 5000 Model 200 Series without any graphics. Code name 3MAX. (5000/260 3MAX+)

DECsystem 5100

A desktop uniprocessor entry-level server. It replaced the DECsystem 3100. Code name MIPSMATE.

DECsystem 5400

A pedestal uniprocessor system based on the

Q-Bus The Q-bus,Schmidt, Atlant G.,Unibus,Q-Bus and VAXBI Bus, in ''Digital bus handbook'', Di Giacomo Joseph Ed., McGraw Hill, 1990 also known as the LSI-11 Bus, is one of several bus technologies used with PDP and MicroVAX computer systems previo ...

. It shared many hardware options with the 3x00-series MAYFAIR VAXes, including TK70 tape drive, MS650-BA memory and DSSI disk drives. SCSI was not available except with third party add in hardware. The unit shipped with a MicroVAX diagnostic processor, which would run similar ROM diagnostics to the MicroVAX series, as well as boot the tape based MicroVAX Diagnostic TK70 tape. Once the console transferred control of the computer to the MIPS processor the MicroVAX sat essentially unused until the next boot. Code name MIPSFAIR.

DECsystem 5500

A pedestal uniprocessor system based on the

. It replaced the DECsystem 5400. The 5500 came with native SCSI support, as well as support for DSSI disk drives. Code name MIPSFAIR-2. The DECsystem 5500 is shipped in a BA430 enclosure, which provides a 12-slot backplane and room for four mass storage devices. The base system contains the following: * A KN220-AA module set. This consists of a KN220 I/O module in slot 1 and a KN220 CPU module in slot 2. The CPU module contains: o 30 MHz R3000 CPU with R3010 FPU. o 512 kBytes of Prestoserve (NFS accelerator) battery backed RAM. The I/O module contains: o Q22-bus interface o SGEC Second Generation Ethernet Controller o DSSI Digital Storage System Interconnect port o SII-based SCSI port. * From 1 to 4 MS220-AA 32MB memory modules, installed in slots 3 through 7.

DECsystem 5800 Series

The DECsystem 5800 Series are high-end

multiprocessor Multiprocessing is the use of two or more central processing units (CPUs) within a single computer system. The term also refers to the ability of a system to support more than one processor or the ability to allocate tasks between them. There ar ...

systems. The series comprised the DECsystem 5810, 5820, 5830, and 5840, with the third digit referring to the number of processors. These systems can be considered to be the MIPS/RISC alternatives of the

VAX 6000 The VAX 6000 is a discontinued family of minicomputers developed and manufactured by Digital Equipment Corporation (DEC) using processors implementing the VAX instruction set architecture (ISA). Originally, the VAX 6000 was intended to be a mid-ra ...

operating the XMI and BI bus.Computergram. "DEC Announcements". Computer Business Review. 12 July 1989.
/ref> The 5810 and 5820, using 25 MHz R3000 microprocessors and R3010 floating-point coprocessors, were introduced on 11 July 1989. Code name ISIS.

DECsystem 5900 and DECsystem 5900/260

The DECsystem 5900 and DECsystem 5900/260 are rack-mounted DECstation 5000 Model 240 and DECstation Model 260 workstations, respectively, positioned as mid-range servers by Digital. The DECsystem 5900 was introduced in early December 1991.Craig Stedman. "DEC adds RISC/Unix stations". Electronic News, December 9, 1991.
/ref> Both models were discontinued on 28 January 1994. Their intended replacement was the DEC 3000 Model 800S AXP packaged in a similar rack-mountable enclosure. The DECstation system module is repackaged in a CPU drawer, which is mounted in a rack with a mounting kit which permits the drawer to be slid in and out. The CPU module also contained an integrated TURBOchannel Extender, the power supply and a blower, which cooled the system. However, as the system module that these systems use does not feature multiprocessing capabilities, the presence of two CPU drawers in a rack simply meant that there were two separate systems. The mass storage drawers, in such a case, would be divided between the CPU drawers, with a minimum of one per a CPU drawer. There are two models of mass storage drawers. One model may contain one to four 5.25-inch full-height non-removable, one 5.25-inch full-height removable or non-removable and two 5.25-inch half-height removable devices. The other model may contain one to five 5.25-inch full-height non-removable, one 5.25-inch removable and two 5.25-inch half-height removable devices. In both models, a 400 W power supply is located at the rear of the drawer. The H9A00 enclosure, a

19-inch rack A 19-inch rack is a standardized frame or enclosure for mounting multiple electronic equipment modules. Each module has a front panel that is wide. The 19 inch dimension includes the edges or "ears" that protrude from each side of the equ ...

, contains a minimum of one CPU drawer and one mass storage drawer. A power controller at the bottom of the enclosure distributed power to the CPU and mass storage drawers. The rack can contain a maximum of two CPU drawers and four mass storage drawers. The DECsystem 5900 has a width of 61 cm (24 in), a height of 170 cm (66.9 in), a depth of 86.4 cm (34 in) and a weight of 265 to 485 kg (480 to 1,070 lb) depending on the configuration.

References

External links

Notes on System Models
{{DEFAULTSORT:Decsystem DEC computers