The VAXstation 4000/90, code named Cougar, is the successor to the
VAXstation 4000/60,
three times faster with its 72MHz NVAX processor with 256KB of L2 cache.
Since it shares the case, memory boards and 3D graphics options with the VAXstation 4000/60, one could consider it a simple processor replacement. Nothing could be further from the truth: the VAXstation 4000/90 is actually a brand new design, with the constraints of having to share form factor (and connector position) with the VAXstation 4000/60, which turned out to be quite challenging.
This machine was so successful that faster models were made: 83.3MHz VAXstation 4000/90A, and 100MHz VAXstation 4000/96.
Since it shares the case, memory boards and 3D graphics options with the VAXstation 4000/60, one could consider it a simple processor replacement. Nothing could be further from the truth: the VAXstation 4000/90 is actually a brand new design, with the constraints of having to share form factor (and connector position) with the VAXstation 4000/60, which turned out to be quite challenging.
This machine was so successful that faster models were made: 83.3MHz VAXstation 4000/90A, and 100MHz VAXstation 4000/96.
Pictures
(Click on the pictures to get larger resolution images)
The VAXstation 4000/90 uses the same `light' plastic case as the VAXstation
4000/60. The heaviest part inside is very likely the power supply on the left
side.
The back of the machine is set up in a 3x3 grid, with two grid cells unused.
The connectors are then:
Centronics SCSI-2 connector | ||
Option connector: either a synchronous serial port, or a TURBOchannel slot | Framebuffer connector: usually 3W3, two on dual-head cards, and sometimes with a VGA-compatible HD15 connector as well | Power supply connectors |
Remote keyboard and mouse cable (male DB15 connector), local mouse (mini-DIN) and keyboard (4P4C `RJ9') connectors | Console or printer port (MMJ), modem or printer port (DE25 female RS232) | Ethernet connector: either 10base5 (AUI) or 10base2 (BNC), with selector switch in-between |
There are also connectors in the front of the system, once you flip the little
door on the right side.
From left to right, they are:
- 4P4C handset connector
- handset/internal speaker selector switch (here shown in the handset position)
- HALT button
- serial/glass console S3 switch (here shown in the serial console position)
- Eight diagnostic LEDs in two blocks of four
The top of the case is kept in place by two tabs, which are easy to unlock.
The bowels of the machine are quite crowded, although this one does not have
a CD-ROM or tape drive.
Note the internal devices brackets are made of plastic, too.
With the internal device trays removed, here is a better look at the
motherboard. Note the daughter board on the right side.
The daughter board simply sports the front connectors, as well as the internal
speaker; or, to follow the inscription on the board itself, the `lights and
switches'. PV2 probably stands for PVax 2, which was the
codename of the
VAXstation 4000 VLC... although the VLC
uses a different daughter board!
With all connectors and boards unplugged, the logic board slides and be
extracted from the case, for a better look.
The connectors on the back of the motherboard are protected with a plastic
cover. It will gently slide to reveal the naked motherboard.
Note the white power supply connector to the left: it is quite unusual, as the
power supply is directly plugged to the motherboard.
The white connector in the middle is a frame buffer connector for VAXstation 4000/60 compatible graphics (SPXg or SPXgt). Below it, the black connector is a frame buffer connector for the native graphics (LCSPX). Over the right half of the white connector, the other black connector is the TURBOchannel option connector. The TURBOchannel option board connects there, and provides a TURBOchannel slot facing the option slot in the back of the enclosure.
On the right, over the processor which is easy to spot with its heatsink, the blue connector is the internal SCSI connector, and the black connector next to it accepts the synchronous serial port DSW21 option.
Unlike the VAXstation 4000/60 motherboard, there is no on-board memory; on the other hand, there are eight memory slots instead of six, with memory installed in sets of four memory boards.
The white connector in the middle is a frame buffer connector for VAXstation 4000/60 compatible graphics (SPXg or SPXgt). Below it, the black connector is a frame buffer connector for the native graphics (LCSPX). Over the right half of the white connector, the other black connector is the TURBOchannel option connector. The TURBOchannel option board connects there, and provides a TURBOchannel slot facing the option slot in the back of the enclosure.
On the right, over the processor which is easy to spot with its heatsink, the blue connector is the internal SCSI connector, and the black connector next to it accepts the synchronous serial port DSW21 option.
Unlike the VAXstation 4000/60 motherboard, there is no on-board memory; on the other hand, there are eight memory slots instead of six, with memory installed in sets of four memory boards.
Here is the processor without its heatsink.
The clock source to its topleft corner runs at 286MHz, which yields a 71.5MHz
processor speed (or the advertised 14 nanosecond clock cycle).
Here is a closer look at the LCSPX default frame buffer option.
Links
- VAXstation 4000 Model 90 Service Information
Detailed description of the machine components, how to replace them, and how to interpret selftest results.
Download (1,476,608 bytes pdf) from: SysMan's VMS site - local copy
- The VAXstation 4000 Model 90
Ten page article published in Digital Technical Journal in 1992, written by the machine's designers, explaining their goals, the problems they faced, and how they delivered a successful design in time.
Download (65,719 bytes pdf) from: Maciej W. Rozycki's archives - local copy