HP 9000 and PA-RISC Computers Story


The HP 9000 Series were a set of technical servers and workstations sold for almost three decades by HP and included a diverse platforms of Unix computers. Both RISC and Unix were developed into coherent products during the 1980s, moving from academia via industrial R&D to productization at a time when much computing was still done on mainframes, minicomputers and time-sharing machines such as DEC PDP, VAX, IBM AS/400 and System/360.

PA-RISC computer period table
Period Series Classes
I Infancy: Late 1980s
HP 9000 800 Early systems
Other HP 9000 300, 400, 500, 600
II Growth: 32-bit 1990s
HP 9000 700 Original workstations
Technical desktops
Small systems
HP 9000 800 E-Class, F/G/H/I-Class
Mainframes 890
III Maturity: 1990s heydays
HP 9000 700 Newer 712 and 715
VME control systems 740s
Visualize workstations B-Class
Lettered servers A-Class
D-Class, R-Class, K-Class
L-Class and N-Class
S-Class, X-Class Convex
Mainframes T-Class
IV Decline: 2000s
Integrity and Itanium rp servers
rx servers
Itanium workstations
Mainframes Superdome

HP 9000 and the PA-RISC series were HP’s new line of products in that fledging market in the early 1980s.. This page focuses on this PA-RISC part of that story, divided into four periods from the 1980s to the 2000s:

I. Infancy: HP moved into the fledging microcomputer market in the 80s with several differently positioned platforms. PA-RISC computers of the HP 9000 Series 800 were HP’s RISC entry into that market. The other, CISC, HP 9000 offerings were sold by HP in parallel for almost a decade.

II. Growth: The 1990s were the main period of HP 9000 and PA-RISC, were much of the major growth and maturity took place. The HP 9000 Series 700 workstations were released and quickly gained traction as a platform for Unix-based graphics, engineering and R&D.

III. Maturity: Many products were released and the line-up matured during the 1990s, from small desktops to large server cabinets and mainframe-type computers, under increasing complex brands and series names. PA-RISC moved from 32-bit to 64-bit with the revamped PA-8x00 processors.

IV. Decline: HP slowly transitioned to a post-RISC phase in the 2000s, with the VLIW Itanium IA64 architecture sold in parallel to its still popular rp series of Integrity PA-RISC servers. As a result of that and a changing market environment, PA-RISC slowly was phased out of the technical HP line-up.

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HP 9000 800

The original series of PA-RISC computers were the HP 9000 800s servers from the late 1980s. They consisted of a variety of computers based on PA-RISC 1.0 and 1.1 designs, the system architecture rather divergent to the 700s workstations, with different chipsets, buses and I/O devices. The distinction between the 700 and 800 series was not as clear cut in the early days however — with the 825S marketed as minicomputer and the very similar 825SRX as superworkstation.

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HP 9000 700

A large range of PA-RISC workstations was sold by HP from the 1990s on with the HP 9000 700 series. These soon became popular 32-bit Unix workstations on a RISC platform, and used HP’s own new processors like the PA-7000, PA-7100 and PA-7100LC. At that time, much technical computing moved to Unix and RISC workstations, superseding older CISC computers. These new workstations were often used for CAD, CAM and specialized software and applications for HP-UX or Unix. As HP acquired Apollo Computers around the time, the Apollo name and technology was part of some workstations, sometimes called HP Apollo 9000.

Around that timeframe, the Precision RISC Organisation (PRO) industry consortium was formed by HP and Convex (in 1992) to support and promote its PA-RISC architecture. Joined over the years by Hitachi, Stratus, Hughes, Mitsubishi Electric, Oki Electric, Prime Computers, Sequoia and Yokogawa, PRO aimed to ensure compatibility between PA-RISC computers and system implementation with testing, conformance and certification programs. This included API and ABI standards for PA-RISC between those systems. On the hardware side, PA-RISC chips and designs were not usually shared with third-parties, licensing and distribution was tightly controlled by HP to partners in the PRO. Some HP 9000 workstations and servers were sold by PRO members rebadged as OEM in their markets.

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Visualize Workstations

From the mid-1990s on, HP sold its PA-RISC workstations with lettered class names: the B, C and J-Class systems. Most of them were sold with Visualize branding as part of the HP 9000 700 series. They were were geared towards graphics and engineering applications such as CAD or CAM, and often used with HP’s powerful Visualize or Visualize-FX range of graphics adapters. Processors were almost the whole range of PA-RISC CPUs from 32-bit PA-7200 up to 64-bit PA-8900.

After the 712 and 715 models, which became broadly available at the turn of the century, workstations from these lettered series’ were among the most popular sold and later re-sold on second-hand and hobbyist markets. They have a support base in open source operating systems, though the earlier HP 9000 700 workstations had the advantage of having had much earlier R&D operating system support in academia and the industry.

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Lettered servers

In parallel to the workstations, HP 9000 servers were renamed with lettered designators and included a spectrum of different 32- and 64-bit PA-RISC computers. These servers were quite powerful at the time of the 1990s with diverse configurations and designs, from the small A-Class to the mid-size D-Class and cabinet-size K-Class. Also during that time, the system architecture between 700s workstations and 800s servers began to converge, only to start diverging again in the late-1990s with the Cell and Stretch architectures, when HP moved to hardware virtualization.

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VME control systems

The 740s VME-based PA-RISC computers were part of the HP 9000 700 series, sold from the early to late 1990s, and used for medical, industrial and military data measurement and real time control, utilizing the VME bus. Processors included 32-bit PA-RISC PA-7100, PA-7100LC and PA-7300LC together with standard HP LASI and ASP chipsets and only some custom VME designs. Operating systems were native HP-UX and HP-RT, the latter for real-time applications, with some open source support.

They closely mirrored corresponding HP 9000/715 and B-Class workstations computers, but packed those electronics onto a single-board VME modules. The VME boards were single boardcomputers, with the HP 9000/742i, 743i and 744. Some of these were integrated into Computers, like the HP 9000/745i and 745. Some were also used in ruggedized VME computers with VME slots, such as the HP 9000/747i, 748 and 748i.

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The label mainframe is used rather broadly here to include all larger HP PA-RISC computers with a large amount of computing resources that were either multi-processor or cluster-type systems. Some were HP’s own development, like the T-Class, an outgrow of the original 800 series servers, and the later Superdome, while others were either co-developed or acquired externally, like the SPP Exemplar architecture from Convex.

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HP renamed its PA-RISC servers again in the early 2000s into the rp series, and shifted the focus of PA-RISC more towards servers with that move. The rp servers were based on 64-bit PA-RISC processors from the PA-8500 to the PA-8800, all multi-processor. Only the first rp branded systems shared design features with contemporary workstations and older servers, while the rest were new, server-only designs.

With the rp range HP moved its PA-RISC offering closer to the new Itanium architecture, which were called rx. Product and technical design was similar between rp and rx, and the PA-RISC rp moved strongly towards Itanium design with the zx1 chipsets and upgrade paths to IA64 processors. The rp were the last line of PA-RISC servers.

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Around the turn of the century, HP started to offer servers and workstations based on Itanium IA64 technology, a VLIW architecture jointly designed with Intel. System architecture between the PA-RISC rp and IA64 rx servers converged with similar designs and chipsets. The zx1 chipset and Itanium buses were used and Itanium slowly phased out PA-RISC from HP’s technical and Unix lineup, albeit at least half a decade later than originally planned.

This was the end of the PA-RISC platform at HP, which vanished with diminishing market share until the mid-2000s. The process of the long decline of RISC and commercial Unix servers was already underway then, which were relegated to special applications and later to high-end, mission-critical servers. HP started withdrawing from Unix workstations before Itanium, but pared down its offering even further under the new CPU architecture. Shipments of Itanium workstations ceased two years after release, at the time when Intel moved the x86 architecture to 64-bit. Originally envisaged as an industry-changing architecture, Itanium changed to be only marketed as alternative to other RISC platforms, and marked the end-phase of HP Unix and RISC platforms.

On a side tangent of history, HP inherited both DEC Alpha RISC and OpenVMS through its acquisition of Compaq in the early 2002, both having been rivals for HP platforms for decades. After discontinuing DEC Alpha, OpenVMS was to find a new home with the Itanium platform at HP, to which it was ported around 2005 to run on HP rx servers, being the first computers to offer both HP-UX and OpenVMS.

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Other series

There were a few other computer series offered under the HP 9000 label before PA-RISC computers were released. This includes early Unix platforms from HP based on Motorola m68k CISC processors, the HP FOCUS line that preceeded PA-RISC and the HP 3000 minicomputers, that later switched to PA-RISC.

The HP 9000 200 series were the earliest incarnations of HP Unix platforms based on Motorola 68000 , and started life as HP 9826 in 1981, all using the Motorola 68000 processor. Soon followed by other high-end technical desktops, such as the HP 9836, 9816, 9920, 9817 and 9837H, there series was renamed in the early 1980s to HP 9000 200 series, and the individual computers to, for example HP 9000/220 (for the 9920). The 200s also ran versions of HP-UX Unix.

The other series based on Motorola M68k processors was the HP 9000 300 series, sold from the mid-1980s to the early 1990s and also a Unix platform. The 300s had a new, functional design with several distinct boxes for each computer, a design later taken over for the first HP 9000 700s series workstations. The 300 series used Motorola CISC processors from the 68010 up to the -40. Besides HP-UX, the 300 series were supported by a variety of BSD operating systems from the 1980s well into the 2010s, including the mythical 4.4BSD and the OpenBSD/hp300 and NetBSD/hp300 siblings.

Related to the 300 series but incorporating technology from the 1989 acquisition of Apollo Computers, the HP 9000 400 series were based on Motorola 68030 and 68040 processors and ran HP-UX and Domain/OS (Apollo Unix). The 400 series were sold in parallel to PA-RISC computers of the 700 and 800 series in the early 1990s, and were widely supported by BSD and open source operating systems. Many designs, devices and peripherals were shared between the Motorola 68000-based 400 series and the PA-RISC 700 and 800 series, including the SGC and EISA buses, SCSI controllers, HP-HIL and HP-IB peripherals, graphics adapters.

The HP 9000/500 computers were the early-1980s predecessors of the PA-RISC workstations and started the HP 9000 series. They were based on a proprietary HP 32-bit processor — the HP FOCUS. First released in 1982, the HP 9000/520, originally 9020, was quickly followed by the HP 9000 530, 540 and 550 computers. Operating system support was limited to HP-UX which on HP FOCUS allegedly was the first commercial Unix supporting a multi-processor, multi-user system.

There was a shortly-lived PA-RISC-based HP 9000 600 series in the late 1980s. The HP 90000/635SV and 645SV were supposedly server-only versions of the 800 series PA-RISC 1.0 HP 9000/835 and 845. Both were deskside server systems and ran HP-UX. The 600 series moniker was discontinued shortly after with servers taking the 800 and workstations the 700 series.

The HP 3000 line were the HP business minicomputers, first released in 1972, with their own operating system MPE, application stack and distinct customer base. From the late 1980s on, HP 3000 moved to the PA-RISC platform and used systems that were closely based on the HP 9000 800 series. HP 3000 used PA-RISC actually earlier than the widely-popular HP 9000 700 workstation series. The first MPE for PA-RISC release was MPE/XL, the last MPE version was MPE/iX with limited Unix support and POSIX compliance. HP 3000 and MPE have been discontinued since.

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This page is an attempt to unify all the different leads and streams of HP 9000 and PA-RISC into a single story, but simplifications were made. The information on this page is based mostly on existing OpenPA content, but also includes new content and interpretation of other sources. Some pieces were sourced from the great HP Computer Museum, but also from news releases, journals or HP Labs communication.

For release dates of HP 9000 computers and their entry prices, there is also the PA-RISC Timeline page. A tabular overview of HP 9000 PA-RISC systems is on the main PA-RISC Computers section that links to pages with more details for individual systems. The history of PA-RISC processors and system architecture is covered briefly in the PA-RISC Hardware page.

The history of PA-RISC operating systems merits its own article, which is covered in the PA-RISC Operating Systems page. Four main streams of systems are covered — commercial Unix, open source, research projects, and others. Release dates and versions are in more detail on the PA-RISC Timeline.

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