HP 9000 720, 730 and 750
Quick Facts | |
---|---|
Introduced | 1991 |
Period | Growth (II) |
Series | 700 Series |
CPU | PA-7000 32-bit 50/66 MHz |
Caches | 384-512 KB |
RAM | 272 MB (730) 768 MB (750) |
Design | ASP |
Drives | 2 SCSI (720/730) 4 SCSI (750) |
Expansion | 1 SGC, 1 EISA (720/730) 2 SGC, 4 EISA (750) |
I/O | Ethernet SCSI 2 serial parallel HIL |

HP 9000 720, 730 and 750 were the first dedicated 32-bit PA-RISC workstations, released in 1991.
Called Snakes, they were based on the first PA-RISC 1.1 processor, the PA-7000 (PCX-S), which was designed to power low cost high performance
workstations.
The Snake workstations were designed for graphics and technical computing, so many I/O controllers and interfaces were integrated into the system, such as NCR SCSI, HP graphics and Intel Ethernet networking.

The new look
industrial design of 720 and 730 workstations was done by ZibaDesign and Roche-Harkins as a design framework
for a new family of workstations
.
The cases were very solid and used interlocking modules, sliders, for I/O components such as storage, which connected to the main I/O board with a short external cable.
720 and 730 share the same backplane and I/O board which could be upgraded through the exchange of the CPU system board.

HP 9000 720, 730 and 750 were widely used by the US Navy through the TAC-3 (Tactical Advanced Computer) framework for military applications, including electronic intelligence gathering (ELINT).
Later HP 9000/735 workstations share a similar case and system setup as the Snakes: 720 and 730 CPU and I/O boards can be swapped for 735 boards for a system upgrade, and vice versa (735 I/O boards do not work with 720 CPU boards).
- HP 9000 720 were introduced in 1991 for $15,890
- 720 CRX Color 2D/3D Workstation for $22,890
- 720 PVRX Color 3D Workstation for $34,390
- Upgrade to 730, CPU board $9,000
- HP 9000 730 were introduced in 1991 for $21,890
- 730 CRX Color 2D/3D Workstation for $28,890
- 730 PVRX Color 3D Workstation for $40,390
- HP 9000 750 were introduced in 1991 for $43,090
- 750 PVRX Color 3D Workstation for $118,090
- 750 TVRX Color 3D Workstation T4 for $58,090
- 112MB additional RAM for $39,200
Especially the more affordable 720 and 730 workstations were widely used in the Unix world of the 1990s, in academia and industry for technical design and computing. Due to their popularity, many operating systems run on Snakes workstations and were ported to it, including research and development projects such as OSF/1 and a variety of Mach.
Architecture
Processors
System | CPU | Speed | L1 cache |
---|---|---|---|
HP 9000 720 | PA-7000 PA-RISC 32-bit | 50 MHz | 384 KB off-chip |
HP 9000 730 | PA-7000 PA-RISC 32-bit | 66 MHz | 384 KB off-chip |
HP 9000 750 | PA-7000 PA-RISC 32-bit | 66 MHz | 512 KB off-chip |
Chipset
- HP ASP chipset
- HP Viper memory and I/O controller as VLSI chip
- Address buffer/controller, 64-pin VLSI CMOS chip
- NCR 53C700 8-bit single-ended SCSI-2
- Intel 82596DX 10 Mbit Ethernet controller
- Intel 82C501AD Ethernet transceiver
- Intel 82350 EISA bus adapter chipset (EISA to GSC)
- Other I/O (serial, parallel, i8042)
- Graphics through separate boards:
System buses
- PBus processor/memory bus at full processor clock with 260 MB/s max data rate
- VSC main system (TTL) bus at half processor clock with 132 MB/s max data rate
- GSC I/O bus
- SGC, expansion of the main VSC bus to SGC expansion cards
- EISA, expansion I/O bus for standard I/O cards
- SCSI-2 narrow single-ended bus
Expansion
Memory
- HP proprietary memory modules, based on DRAMs with error detection and correction (EDC), some shared with 735/755
- 720 8 slots
- 730 8 slots and 16 MB onboard, 272 MB (8×32+16) maximum
- 750 12 slots, 768 MB (12×64) maximum
I/O slots
- 720/730
- One SGC expansion slot for SGC cards (DIO-II formfactor)
- One EISA slot for EISA cards
- 750
- Two SGC expansion slots SGC cards (DIO-II formfactor)
- Four EISA slots EISA cards
Storage
- 720/730 Two SCSI 3.5″ Narrow SE 50-pin hard drives
- 750 Two SCSI half-height 5.25″ Narrow SE 50-pin SCSI drives and two SCSI full-height 5.25″ Narrow SE 50-pin SCSI drives
I/O ports
- SCSI-2 50-pin single-ended
- Two serial RS232C DB9 (up to 115200 baud)
- Parallel DB25
- 15-pin AUI 10 Mbit & 10Base2 BNC Ethernet
- Graphics depend on installed SGC framebuffer
- HP-HIL connector for input devices
- Jack for beep audio
- Ten LEDs on the front for errors and status messages
Operating systems
- HP-UX, the original HP Unix shipped with it
- HP-UX 11.00 in 32-bit mode, might work but unsupported
- HP-UX 10.20 32-bit
- HP-UX 10.00 and HP-UX 10.10, pre-Y2K
- HP-UX 9 (9.01, 9.03, 9.05, 9.07), pre-Y2K
- HP-UX 8 (8.01, 8.05, 8.07), pre-Y2K
- PA-RISC Linux, main Linux port to PA-RISC
- OpenBSD, open-source Unix-like, ported to PA-RISC
- NetBSD, open-source Unix-like, ported to PA-RISC
- 720 OSF MK-PA, OSF/1 Unix port to PA-RISC
- HPBSD, original 4.3BSD Unix on PA-RISC (closed)
- Mach 4/Lites, research microkernel with 4.4BSD (with issues)
- MkLinux, research Linux with Mach microkernel
- OSF MK-PA, OSF/1 Unix port to PA-RISC
Pictures








Benchmarks
System | CPU | SPEC92 int |
SPEC92 fp |
SPEC95 int |
SPEC95 fp |
---|---|---|---|---|---|
HP 9000 720 | PA-7000 50 MHz | 36.4 | 58.2 | 1.20 | 2.00 |
HP 9000 730 | PA-7000 66 MHz | 47.8 | 75.4 | 1.50 | 2.30 |
HP 9000 750 | PA-7000 66 MHz | 48.1 | 75.0 | 1.50 | 2.30 |
Compared to SPEC benchmark data, HP 9000 720, 730 and 750 had similar speed to other contemporary Unix workstations and were faster than Intel 486DX2 and level with Pentium at the same clock but significantly faster in floating point.
System | CPU | SPEC92 int |
SPEC92 fp |
SPEC95 int |
SPEC95 fp |
---|---|---|---|---|---|
HP 9000 755/125 | PA-7150 125 MHz | 136.0 | 201.0 | 3.97 | 4.61 |
Intel | Intel Pentium 75MHz | 89.1 | 68.5 | 2.31 | 2.02 |
DEC AlphaStation 200 | DEC Alpha 21064 100MHz | 74.6 | 95.2 | 1.48 | 2.79 |
SGI IRIS Indigo IP20 | MIPS R4000 100MHz | 57.6 | 60.3 | ||
Sun SPARCstation 10 | Sun SuperSPARC 40MHz | 50.2 | 60.2 | 1.13 | 1.38 |
Digital DECstation 5000 | MIPS R4000 50MHz | 43.2 | 42.1 | ||
IBM RS/6000 355 | IBM POWER 41MHz | 40.7 | 83.3 | ||
Siemens PCE-4C | Intel 486DX2 66MHz | 35.8 | 16.1 | ||
Motorola 8000 | Motorola 88100 33MHz | 27.7 | 18.8 | ||
SGI IRIS Indigo IP12 | MIPS R3000 33MHz | 22.4 | 24.2 | ||
DEC 5000/33 | MIPS R3000 33MHz | 20.9 | 23.4 | ||
HP 9000 425e | Motorola 68040 25MHz | 12.2 | 9.3 | ||
Digital VAX4000 | DEC KA46 22MHz | 11.1 | 12.6 |
Documentation
Manuals
- HP Apollo 9000 Model 720/730 owner’s guide, Hewlett Packard (January 1991, A1926-90001) parisc linux
- HP Apollo 9000 Model 750 owner’s guide, Hewlett Packard (June 1991, A1961-90000) parisc linux
- Installation Guide for HP Apollo 9000 Model 720/730 Workstations and Servers, Hewlett Packard (May 1991, A1926-90000) hpmuseum
- Precision Architecture RISC Diagnostics Manual, Volume 1, Hewlett Packard (August 1991, 09740-90041) hpmuseum
- HP Apollo 9000 Series 700 Workstations/Servers CE Handbook, Hewlett Packard (June 1991, A1926-90003) hpmuseum
LED messages
- LED errors and status messages might be displayed on the HP 9000 720, 730 and 750 front LEDs
Product sheets
- HP Apollo Series 700 Model 720 Workstation, two pager, Hewlett Packard (1991, 5091-0974E) hpmuseum
- HP Apollo Series 700 Model 720 Workstation, product brief, Hewlett Packard (1991, 5091-0977E) hpmuseum
- HP Apollo Series 700 Model 730 Workstation, two pager, Hewlett Packard (February 1991, 5091-0975E) hpmuseum
- HP Apollo Series 700 Model 730 Workstation, product brief, Hewlett Packard (1991, 5091-0979E) hpmuseum
- Feel the Power of PA-RISC Workstations, product brief, Hewlett Packard (1991, 5091-0986E) hpmuseum
- HP Apollo Series 700 Model 750 Workstation, two pager, Hewlett Packard (Januar 1992, 5091-3188E) hpmuseum
- HP Apollo Series 700 U.S. Price Guide, Hewlett Packard (1991, no #) hpmuseum
- The Best RISC Workstations in the Industry, Hewlett Packard (February 1992, 5091-0983E) hpmuseum
Articles
- System design for a low cost PA-RISC desktop workstation, R. Horning et al, COMPCON Spring '91 Digest of Papers, 1991
- CMOS PA-RISC processor for a new family of workstations, M. Forsyth et al, COMPCON Spring '91 Digest of Papers, 1991
- Hewlett-Packard Journal August 1992 archive.org
- Midrange PA-RISC Workstations with Price/Performance Leadership, page 6 (Andrew J. DeBaets and Kathleen M. Wheeler)
- HP 9000 Series 700 Workstation Firmware (IODC, PDC) page 9 (Deborah A. Savage)
- VLSI Circuits for Low-End and Midrange PA-RISC Computers, page 12 (Craig A. Gleason et al.)
- HP 9000 Series 700 Input/Output Subsystem, page 26 (Daniel Li and Audrey B. Gore)
- Design Verification of the HP 9000 Series 700 PA-RISC Workstations, page 34 (Ali M. Ahi et al.)
- Mechanical Design of the HP 9000 Models 720 and 730 Workstations, page 43 (Arlen L. Roesner and John P. Hoppal)
- Meeting Manufacturing Challenges for PA-RISC Workstations, page 49 (Spencer M. Ure et al.)
- HEWLETT-PACKARD UNLEASHES ITS RS/6000 KILLERS, Tech Monitor archive, March 26, 1991
- Snake In the Box, Unix World May 1999, Volume VIII, Number 5, page 79 archive.org
- High Performance PA-RISC Snakes Motherboard I/O , Hewlett-Packard 1993, bitsavers
- HP Apollo Series 700 Performance Brief, Hewlett Packard (October 1992, 5091-5750E) hpmuseum