VAX 4000
| Company type | Public |
|---|---|
| Industry | Computer hardware |
| Founded | November 7, 1957 in Maynard, Massachusetts, United States |
| Fate | Acquired by Compaq |
| Successor | Compaq |
| Headquarters | Maynard, Massachusetts , United States |
| Products | VAX 4000 series superminicomputers |
The VAX 4000 series represents a now-obsolete line of entry-level superminicomputers created by Digital Equipment Corporation (which later became part of Compaq). These systems utilized microprocessors that executed the VAX instruction set architecture (ISA). Following the MicroVAX lineup, the VAX 4000 ran the OpenVMS operating system and marked the final generation of low-end VAX machines before Compaq ceased production of the platform.
VAX 4000 Model 300
Unveiled on 9 July 1990 at DECworld in Boston, Massachusetts, the VAX 4000 Model 300, also known by its codename "Pele," succeeded the MicroVAX 3800 and 3900 models. It was equipped with the KA670-AA CPU module featuring a 35.71 MHz (28 ns cycle) Rigel chipset, complemented by a 128 KB external secondary cache protected by ECC and constructed from 84 ns SRAM. Memory configurations ranged between 32 and 256 MB, utilizing one to four MS670-BA (32 MB) or MS670-CA (64 MB) modules. Expansion capabilities were provided through the Q-bus interface. Users could upgrade the Model 300 to Models 400, 500, or 600 by swapping out the backplane, CPU, and memory components.
VAX 4000 Model 200
Introduced in January 1991 as an entry-level successor to the MicroVAX 3400, the VAX 4000 Model 200 bore the codename "Spitfire" and was positioned beneath the Model 300 in performance hierarchy. This model incorporated the KA660 CPU module powered by a 28.57 MHz (35 ns cycle) SOC microprocessor and supported memory capacities from 16 to 64 MB.
VAX 4000 Model 500
The VAX 4000 Model 500, codenamed "Omega/N," was launched on 30 October 1991 with availability commencing in December of that year. As the successor to the Model 300, it retained the latter as a more affordable choice. The system employed the KA680 CPU module featuring a high-speed 71.43 MHz (14 ns cycle) NVAX microprocessor alongside a 128 KB external tertiary cache. This model introduced enhanced MS690 memory modules capable of supporting up to 512 MB of system memory with options including 32MB, 64MB, and 128MB modules.
VAX 4000 Model 100
Debuting on 7 July 1992, the VAX 4000 Model 100, known as Cheetah-Q, served as an entry-level offering within the series. It housed the KA52 CPU module running at 72 MHz (14 ns cycle) NVAX microprocessor speed and incorporated a 128 KB external tertiary cache. The maximum memory supported was up to 128 MB.
VAX 4000 Model 400
Also released on 7 July 1992, the mid-range distributed server VAX 4000 Model 400 carried the codename Slow-mega. This model featured the KA675 CPU module with a microcode-throttled NVAX microprocessor operating at 63 MHz (16 ns cycle), paired with a 128 KB external tertiary cache. Its memory capacity ranged from as little as 16 MB up to a maximum of 512 MB.
VAX 4000 Model 600
The top-tier offering within this family, the VAX 4000 Model 600—referred to as Omega/N+—was introduced on the same day, July 7, 1992. It utilized the KA690 CPU module containing an NVAX microprocessor clocked at an impressive 83 MHz (12 ns cycle) and featured a substantial external tertiary cache of 512 KB. Memory support extended from 16 MB to as much as 512 MB via MS690 modules.
VAX 4000 Model 100A
Continuing the Cheetah-Q lineage, the Model 100A was launched on October 12, 1993. It retained the KA52 CPU module running at a frequency of 72 MHz (14 ns cycle) NVAX processor speed and included a tertiary cache of 128 KB while supporting up to a maximum of 128 MB memory.
VAX 4000 Model 500A
The Model 500A, internally referred to as Omega/N, was released on 12 October 1993. It incorporated the KA681 CPU module, which housed a 71.43 MHz (14 ns) NVAX microprocessor alongside a 128 KB tertiary cache.
VAX 4000 Model 600A
Also launched on 12 October 1993, the Model 600A Omega/N+ utilized the KA691 CPU module. This system was powered by an 83 MHz (12 ns) NVAX processor and included a larger 512 KB tertiary cache.
VAX 4000 Model 700A
The high-end Model 700A, known by the codename Legacy, made its debut on the same date. It featured the KA692 CPU module with a 100 MHz (10 ns) NVAX microprocessor complemented by a substantial 2 MB external tertiary cache.
VAX 4000 Model 105A
Unveiled on 12 April 1994, the Model 105A Cheetah-Q+ incorporated the KA53 CPU module equipped with an enhanced NVAX running at 83 MHz (12 ns cycle). It retained a tertiary cache size of 128 KB and supported memory capacity up to 128 MB.
VAX 4000 Model 505A
Released in late August 1994, the Model 505A Omega/N+ featured an improved NVAX processor clocked at 83 MHz (12 ns) and expanded its external tertiary cache to 512 KB.
VAX 4000 Model 705A
The Model 705A, carrying the codename Legacy+, was introduced in August 1994. It employed the KA694 CPU module with a faster NVAX microprocessor running at 111.12 MHz (9 ns cycle) and included a large external tertiary cache of 2 MB.
VAX 4000 Model 106A
Known as Cheetah-Q++, the Model 106A utilized the KA54 CPU module with a NVAX microprocessor operating at 100 MHz (10 ns cycle). It came with a 512 KB external tertiary cache and was eventually replaced by the VAX 4000 Model 108.
VAX 4000 Model 108
Introduced on 8 October 1996 as the successor to the Model 106A, the VAX 4000 Model 108 (Cheetah-Q++) incorporated the KA57 CPU module featuring a NVAX processor running at 100 MHz along with a 512 KB tertiary cache. This model supported up to 256 MB of memory using standard industry SIMMs, which doubled capacity while lowering costs compared to proprietary SIMMs. Enhancements also included a more compact chassis and improved disk subsystem support. Production ceased on 30 September 2000, with final deliveries completed by year-end.
VAX 4000 Model 50
Designed as an upgrade path for MicroVAX 3x00 or VAX 4000 Model 200 systems, the VAXbrick, or VAX 4000 Model 50, featured the KA600 CPU module equipped with an NVAX microprocessor.