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.

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 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.


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, the system cost almost $8,000.

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.


It 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 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 coprocessor socket for the Intel 80287 chip. That wasn’t a mistake; the 387 wasn’t available yet. A slow 287 coprocessor was faster than none at all.


The 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.

Several competitors offered 386-based computers of their own within months of the Deskpro 386’s release. One early customer was Microsoft. Microsoft developers used them 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.

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.


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.

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