Date of Production: 1990

CPU Type: CISC, 32-bit:

Random access memory: 96 MB

Max. random access memory: 128 MB

SN: AY04000577




I bought that VAX via ebay during 2004. Originally, two DSSI-drives, some CXY08 controllers and a KZQSA-Controller (SCSI) were installed. On the system drive was a version of openVMS 6.x dating back from 1996 installed. The seller was not able to make any comments about the origin of the system and how long it was used, so its story before 2004 remains unknown.

Between the date of acquisition in 2004 and 2010, this VAX was not in use, though I planned 3 years ago to use it as a webserver. This year, I finally had enough time to put a fresh installation of openVMS 7.3 on a DSSI-drive. Moreover, I successfully installed a CMD controller, which serves as a DSSI-to-SCSI-bridge and conntected a SCSI-drive to the VAX for my user-data.

The system runs openVMS 7.3 and webserver software called WASD (version 10) and hosts this website.

Details of the VAX 4000-300:

Here are some detailled pictures about the VAX which is housed in a BA-440 chassis:


The front door is actually made of two separate doors: A lower and an upper one.

Separating the doors allowed for instance the tape drive to be accessed for backups while connectors and the the power switch of the VAX not being accessible for security reasons.

This VAX has currently a TF86 DSSI tape drive and two DSSI drives installed.


The BA440 chassis is structured as follows:

The upper part contains drive units such as harddisks and tape drives which can be of type DSSI.The lower part contains on the right side the power supply, next to it the CPU and memory boards. On the left side is situated the QBUS-slots compartment (part where the long metal bars are mounted).

Let's have a closer look to the different compartments of the of chassis:

Up to four disk drives can be installed, as the slot of the tape drive can be used for a disk drive, too. The TF86 tape drive is actually a SCSI-drive with an additional SCSI-DSSI-converter board. Up to 6 GBytes can be stored on a DLT drive. On the right side of the slot where the tape drive is can be seen two switches: They give possibility to halt the CPU or to reset the VAX. Those switches can be permanently turned off in the console of the VAX by software, in order to prevent users who may have access to the tape drive from halting or resetting the VAX.  

Lower part of the chassis:

From left to right: QBUS expansion slots, CPU/memory slots with panel, power supply.
On the bottom of those three are situated the two large fans which provide cooling.

The heart of the VAX: Behind the right large panel are placed the CPU- and memory boards. The panel provides interfaces such as the serial interface for console access and the setting of its baud rate, connectivity to the two DSSI-busses, a 10Mbit/s Ethernet interface via BNC or AUI.

Left to the CPU-panel are inserted the QBUS-boards for expandability. Here, a SCSI-interface board of type KZQSA is inserted. The VAX CPU-board itself natively did not provide a SCSI-interface.

Up two 7 Q-Bus boards can be added to the system. Very popular where SCSI-interface-boards (that gave possibility to attach an external SCSI CD-ROM drive), expansion boards for serial communication and controller boards for external tape- and/or disk drive subsystems.
Let's have a look behind the metal "curtain":

Removing the panels of the upper compartement of the chassis reveals the two DSSI-drives and the SCSI-DSSI converter of the tape drive, which is left to the drive itself.
The activity-LEDs of the disk drives and their mechanical plugs for the DSSI-bus-ID are conntected via the two small ribbon cables between the drives and the front panel. To the left of the DSSI-drives are two empty drive slots.


Behind the CPU/Memory panel and the qbus slot panels are the boards themselves (what a suprise ;-) ).

The qbus and the CPU/Memory-compartments are separated by a metal plate. Right to that plate is the VAX-CPU-board. Next to the CPU are three memory-boards. Up to 4 memory boards with a total memory of 128MB can be installed, which was much back then.

The CPU-board of the VAX 4000-300:
The CPU is of type "Rigel" (RVAX) and runs at 35 MHz.

One of the L-4001 memory boards with a total amount of 32MB.
The memory boards are densely populated with memory-chips on both sides of the board ! vax4300_disks 
mainboard  This is the SCSI-controller board (KZQSA-SA), using the Q-bus interface.

Let's talk about air-flow:

On the very bottom of the chassis are situated the fans which provide cooling. Those two fans are the only ones in the chassis and can run with low rotational speed due to their large size. Therefore, the VAX 4000 systems do not produce much noise when running.

Backside of the fan tray: The two large NIDEC-fans.

Air is blown from the bottom of the VAX chassis through the boards and the power supply to the upper disk drive compartment of the chassis and then evacuated through the plastic front panels of the drives and through the large slot on the front and the sides at almost top of the chassis, as seen in this picture.