SRX and VRX Graphics on PA-RISC

In the late-1980s, HP developed graphical accelerators for the fledging 3D design market, an outgrowth of MCAD solutions on Unix and PA-RISC. With SRX and VRX graphics systems, external boxes that connected to the main HP 9000 PA-RISC computer, HP tried to compete with other entrants in the 3D and animation markets such as Silicon Graphics.

SRX and VRX, plus the Turbo versions, were developed in the HP-Apollo merger phase for Motorola-based HP 9000 (300 and 400) and new PA-RISC workstations (800, later 700). They were very expensive, not very successful, used for 3D design but also for measurement and the military (weather, satellite data, radar) and supported in HP-UX until 1999.

NASA developed programs for PA-RISC and SRX in the late-1980s, including Graphical Animation Software (GAS) for fluid dynamics, plus some of the other early CAD solutions were modified for or support SRX and VRX.

SRX

SRX was a HP graphics system for HP 9000 HP-UX workstations from the late-1980s. Two versions of the 3D graphics accelerators were provided – plain SRX and the faster Turbo SRX that supported Series 300 (68000-based) and 800 (PA-RISC). Both SRX and TurboSRX were external accelerator boxes that connected with an interface card to the main workstation (SPU) using LGB, the Local Graphics Bus.

HP 835 TurboSRX
HP 835 TurboSRX © 1989 HP

SRX and TurboSRX competed in a market with the likes of Apollo DN1000, AT&T Pixel Machine and Alliant Visualization; which all eventually were outperformed by Silicon Graphics IRIS (4D). HP SRX (and VRX) were still often used for finite element analysis (FEA) and 2D and 3D CAD, with animation and 3D modeling being a lesser HP use case.

HP 825SRX
HP 825SRX © 1987 HP

HP sold SRX and TurboSRX often as integrated workstation packages with the graphics box together with their host SPU and interfaces. Examples are HP 825SRX Superworkstation, a HP 9000 825 from 1987, had graphics performance and visual realism [for] complex designs [...] from different perspectices in real time.

The HP 835 TurboSRX was a special HP 9000 835 from 1989 with TurboSRX offered. This was all before HP introduced dedicated PA-RISC workstations in the HP 9000 700 line, such as 730 and 750 in 1991, which in turn were also offered in intergrated graphics packages (with VRX).

Plain SRX

HP SRX was the basic SRX version for 2D and 3D design acceleration for HP 9000 Unix workstations, released in 1987 in HP 9000 800 computers. Besides Series 300 (68000-based), HP offered SRX especially with the HP 9000 825SRX workstation, for extraordinary speed and resolution in 2D and 3D graphics, combining 8 MIP computation power with interactive solid rendering graphics.

SRX was implemented as external graphics box, connecting with an interface to the LGB at the PA-RISC workstation SPU. It offered standard 8-bit (256) color graphics with optional 24-bit (16.7M) colors, in a 1280×1024 resolution and a hardware Z-Buffer.

HP 9000 825SRX workstations were, in 1987, top of the new class of [superworkstations] with high computational and bit-mapped graphics performance. Use cases for 825SRC were mechanical engineers in 3D solid modeling for applications such as conceptual design, visualization, analysis, testing and finite-element modeling and analysis.

TurboSRX

HP TurboSRX Starbase
HP TurboSRX Starbase © 1989 HP

HP TurboSRX was the advanced SRX version for 3D acceleration, consisting of an external box and connection to Unix workstations with LGB interface. HP introduced the TurboSRX 3D graphics system in 1988 for its HP 9000 350 (Motorola) and 835 (PA-RISC) Unix computers.

TurboSRX had the most advanced and extensive feature set available in its price range, informed by popular MCAD solutions on HP workstations. A 835 TurboSRX system went for $91,500 in 1991.

TurboSRX consisted of a completely separate box, attached to the SPU. This Display Controller contained several boards to make up the TurboSRX adapter, attached with 32-bit Local Graphics Bus (LGB) interface to the SPU that allowed direct memory access.

TurboSRX used custom HP VLSI chips for floating point (adder/subtractor, divider, multiplier) and included the TREIS chip in NMOS-III, all fabbed by HP. HP lated moved to i860 RISC accelerators on the VRX and TurboVRX.

TurboSRX provided a standard 8-bit (256) color graphics with optional 24-bit (16.7M) color graphics, rendered in 1280˜1024 resolution. It had a hardware Z-Buffer, graphics transform engine, scan converter, frame buffer controller, frame buffer and color map for fast solids modeling. Graphics library support included Starbase and PHIGS, both on HP-UX.

A 835 with TurboVRX had a performance of around 240,000 vectors per second and 32,000 polygons, slightly below contemporary SGI 4D and Iris offerings (and SPARC too).

Apparently, there was a TurboSRX Animation version too.

VRX

HP VRX, Virtual Rendering for X, was a graphics subsystem introduced by HP in the late 1980s for its HP 9000 Apollo workstations. There were at least three different versions of VRX – Entry-level VRX, Personal VRX (PVXR) and Turbo VRX (TVRX), with PVXR and TVRX brought over from 400 Series (Motorola) to PA-RISC like the 730 and 750 workstations.

HP VRX
HP VRX © 1991 HP

Personal VRX and Turbo VRX were introduced by HP in 1990 for the 400 series and bought to PA-RISC in 1991. If you’re interested in rendering, realismm or solids modeling, the PersonalVRX or TurboVRX options are designed for you.

HP opted to not use the EISA bus for VRX adapters due its slower speed [which] might impede graphics performance, but chose its own SGC bus for this instead. VRX graphics were supported in HP-UX until HP-UX 10.20 younger than ACE 0699 and were not to be used with X servers or patches after February 1999.

VRX graphics were all to be used with 19″ CRT monitors and 1280×1024 resolution.

Entry-level VRX

HP Entry Level VRX (EVRX) was the initial VRX graphics offering from HP for 3D acceleration of HP 9000 300 and 400 Motorola-based workstations. EVRX contained one 33 MHz Intel i860 RISC graphics accelerator for 8-bit graphics with 256 colors and a 1280×;1024 resolution. It was not available for HP 9000 700 or PA-RISC.

Personal VRX

Personal VRX (PVRX) was a HP graphics adapter that featured one 33 MHz Intel i860 RISC processors, available for HP 9000 700 PA-RISC workstations with SGC bus. PVRX provided 8-bit graphics for 256 colors, a resolution of 1280×1024, a 16-bit Z-buffer and 24-plane dithering for solid-rendering 3D graphics with dynamic shading [...] a necessary feature in the MCAD and MCAE markets.

PersonalVRX was available in three performance options: P1 (eight planes), P2 (eight planes) and P3 (16 planes), with it seems that latter (P3) the default option for PA-RISC. PVRX was offered with HP 9000 720, 730 and 750 workstations.

Turbo VRX

Turbo VRX (TVRX) was the top-of-the-line HP graphics accelerator for PA-RISC workstations, for specific graphics applications in mechanical engineering and scientific analysis. It also adds such features as antialiasing, alpha blending, and texture mapping. It consisted of the Display Controller, a separate box, that connected to an SGC I/O card in the PA-RISC workstation, the host interface.

TurboVRX uses three or four 40 MHz Intel i860 RISC processors as graphics accelerators. It was capable of 24-bit graphics (16.7M colors) in a 1280×1024 resolution on 16″ or 19″ CRT monitors. TurboVRX had a 24-bit Z-buffer for 3-D anti-aliasing and supported X11/PHIGS, X11/Starbase and X11/GKS graphics libraries.

TurboVRX was available in three performance options, T1 (one i860), T2 (two i860) and T3 (three i860), later upgraded in 1991 to four (T4). TVRX was shipped with HP 9000 750 for interactive solid modeling and 3D rendering, for an easy $118,190 in 1991 (T4 configuration) and in many other configurations with 720 and 730 workstations.

Product numbers

Part numbers of some SRX and VRX adapters and boxes

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Documentation

Other

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