Compaq Deskpro 386

The Compaq Deskpro 386, announced in September 1986, was a landmark IBM PC compatible computer. The first fully 32-bit PC based on the Intel 386, its release took the leadership of the PC ecosystem away from IBM, and Compaq became the leader.

Compaq was no upstart by 1986. Its Compaq Portable was a runaway success earlier in the decade, and Compaq was a darling of the industry. The Deskpro 386 solidified Compaq’s position as an industry innovator.

Compaq Deskpro 386
By releasing the 32-bit Compaq Deskpro 386 in 1986, Compaq seized leadership of the PC market from IBM. IBM never recovered.

The Compaq Deskpro 386 wasn’t as revolutionary as it sounded, but it didn’t need to be. Software that would have felt its weaknesses was still years away. It was basically a 286 clone with enough changes to make a 386 CPU work. It originally came with a 16 MHz 80386 processor. Speed-wise, it was about three times as fast as a 6 MHz 286-based IBM PC/AT, and twice as fast as the fastest available 286 systems of the time.

Intel released the 386 processor in October 1985. It was available in volume by June 1986.

Compaq wasn’t shy about predicting the machine’s significance. At introduction, if IBM didn’t release a 386-based machine within six months, Compaq president Rod Canion predicted, the Deskpro 386 would become the industry standard. It took seven months for IBM to respond with its PS/2 Model 80, and the Deskpro 386 did indeed become the standard.

Compaq Deskpro 386 Pricing

The base price was $6,499 for a system with 1 MB of RAM, MS-DOS 3.1, a single 1.2 MB floppy drive, and a 40 MB hard drive with a 30-ms seek time. The price didn’t include a monitor or video card. A basic CGA/monochrome video card was $199 and an EGA card was $599. A color monitor was $799. By the time you added the video card and a monitor, a complete system cost almost $8,000. In 2017 dollars, that would be nearly $18,000.

This was expensive for the time, but it only represented a 23 percent premium over an IBM PC/AT even though it was twice as fast as a PC/AT. Reviewers in 1986 acknowledged the high price but argued that the performance offered good value, if you needed the performance.

Compaq Deskpro 386 Specifications

Compaq Deskpro 386
Intel started shipping 386 CPUs in volume in June 1986. Compaq used the new chips to build a workstation-class PC, forcing IBM’s hand and taking leadership of the PC industry.

The Compaq Deskpro 386 had a 32-bit expansion slot for RAM (it could use up to 14 megabytes), four 16-bit slots and three 8-bit slots. All but the 32-bit slot were ISA. The Deskpro 386 came with a 32-bit memory board with 1 megabyte of RAM from the factory. Five of the slots were open for user expansion.

The presence of 8- and 16-bit slots slowed the system down, but true 32-bit operating systems were still a few years off. It was essentially a fast-for-its-time 16-bit system.

The Deskpro 386 had a math coprocessor socket for an Intel 80287 chip running at 8 MHz. That wasn’t a mistake; the 387 wasn’t available yet. A slow 287 floating point unit was faster than none at all. Once the Intel 80387 hit the market, Compaq revised the design to allow either a 287 or 387 math coprocessor.

The machine had a total of four 5.25-inch storage bays, any of which could hold a 5.25-inch floppy drive, 40-megabyte tape backup, or hard drive. Factory configurations usually included a 1.2-megabyte 5.25-inch floppy drive, and a hard drive of 40, 70, or 130 megabytes.

The Compaq Deskpro 386’s Legacy

The Compaq Deskpro 386 forced IBM to release a 386-based PC. IBM resisted 386 PCs because they would have competed with the IBM 4300-series minicomputers. IBM had a policy of not competing with itself.

Compaq exploited this in its advertising, positioning the Deskpro 386 as an alternative to workstations and minicomputers, touting its similar performance along with the ability to run industry-standard DOS software like Lotus 1-2-3. IBM saw the 386 as a conflict of interest. But for Compaq, building the fastest and most powerful PC possible with 1986 technology was an opportunity. Compaq bet, correctly, that a PC with enough power to compete with professional workstations and backward compatibility with MS-DOS would gain popularity. Compaq predicted in the Deskpro 386 user manual that high-end software previously impractical on PCs would soon follow. It was correct. In 1987, SCO produced XENIX 386, a port of System V Unix that could run on systems like the Deskpro 386, allowing it to function as a high-end Unix workstation or server.

Ultimately, the Compaq Deskpro 386 gave Microsoft and Intel the opening they needed to move from the desktop into midrange and high-performance computing.


Several competitors offered 386-based computers of their own within months of the Deskpro 386’s release. But being first had its benefits. One early customer was Microsoft. Microsoft developers used Deskpro 386s because they were the fastest PCs on the market. As a result, late 1980s and early 1990s Microsoft products like Windows 3.0 ran very well on Compaq hardware. So if you wanted to run Windows, it was a good idea to buy a Compaq.

IBM followed in 1987 with its PS/2 line, which featured a proprietary and uncloneable expansion bus called Microchannel. Compaq responded by working with other clone makers to develop an open competing standard called EISA. EISA wasn’t as good as Microchannel, but price won over capability.  EISA and future open standards like VESA and PCI did win, and eventually even IBM came back.

Collecting the Compaq Deskpro 386

Early 386 machines are highly collectible. They don’t turn up very often, and historically they are very important.

Prior to the 386, proprietary Unix workstations and minicomputers dominated high-end computing. The availability of viable 386 computers made Linux and Windows NT feasible. High-flying names like Digital Equipment Corporation, Sun Microsystems, and even IBM faded over time as a direct result of the 386. The Deskpro 386 was the first of that wave.

With some luck, you may be able to spot a Deskpro 386 or related paraphernalia on Ebay.

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