Compaq Steals a March With 386

RICHARD O'REILLY <i> designs microcomputer applications for The Times</i>

Compaq Computer didn’t invent the 386 personal computer, but the company did beat IBM to market with its high-performance machine by a comfortable margin. And Compaq has continued to challenge Big Blue for supremacy in 386 machines, named for the speedy Intel 80386 microprocessors that serve as the computers’ brains.

With its recent introduction of three more 386 machines, the Houston-based computer maker covers the market nicely.

Recently I tested two of Compaq’s newer models, its blazing 386/25 and the slightly more sedate and affordable 386s. I have not spent any time with the newest model announced last month, the 386/20e, which falls in between the other two in performance.

The 386 class of computers comes in many varieties for two reasons: There are several different versions of the 386 chip, and there is no industrywide standard about how a 386 computer should operate internally.


Thus, Compaq builds its 386 machines so that they are compatible with the expansion circuit boards available for its earlier 80286 computers and with IBM AT-class computers. IBM, on the other hand, adopted a different internal design for its 386 and newest 286 computers that is not compatible with earlier expansion boards.

The Compaq 386/25 is the company’s fastest, most powerful and most expensive computer. It runs at 25 megahertz, a measure of the speed at which the chip processes instructions. The original Compaq and IBM models ran at 4.77 megahertz.

Computer power also reflects how many programs a computer can store, how much memory the programs can use and how much data can be stored. The 386/25 can be equipped with up to 16 megabytes of random access (operating) memory, or RAM, and up to 1.2 gigabytes of hard disk storage. (A gigabyte is 1,000 megabytes, the equivalent of 1 billion characters)

The Compaq 386s, on the other hand, is the company’s least expensive, smallest, slowest and least powerful 386 machine. It is likely to be widely imitated and marketed as an affordable alternative to the older generation 286-class computers, whose performance it easily eclipses.

Less Memory Capacity

The heart of the 386s is Intel’s new 80386SX microprocessor, which can be installed in a less complex and less expensive computer chassis than the standard 386 chip. One reason the 386 chip is so much more powerful than its predecessor is that it can manipulate data 32 bits at a time. The new 386SX does internal processing in the same 32-bit segments, but communicates to the rest of the computer 16 bits at a time, just like the 80286 chips.

The 386s has less capacity than the larger 386/25, with a limit of 13 megabytes of random access memory and 220 megabytes of hard disk storage. Basic models come with just 1 megabyte of memory and 20- or 40-megabyte hard disks.

Speed really depends on what tasks the computer is being asked to perform. I made a stab at some comparisons by setting up a macro, a series of programmed instructions, for an Excel spreadsheet that successively recalculated a series of formulas and painted a variety of charts from the resulting numbers.


When I ran the macro on my AT-clone, which runs slightly faster than a standard IBM PC-AT, it took one minute and 41 seconds. The Compaq 386s did it in 56 seconds while the 386/25 whipped through it in a mere 29 seconds. Those numbers are a good indication of the speed differences that users would find in running a variety of programs.

I didn’t have an opportunity to make the same test on IBM’s hot new PS/2 Model 70, which also sports a 25-megahertz 386 chip. Presumably, the IBM could edge out the Compaq for the fastest time, however, because its circuitry contains a larger speed-up feature--a memory cache--than the Compaq. But the Model 70, which is a small-footprint desktop design, cannot match the Compaq for hard-disk storage and circuit board expansion slots.

I also have not tested the less widely distributed new FlexCache 25386DT from Advanced Logic Research in Irvine, or ALR, which designed the first 386 computer. The model sports the same size memory cache as IBM’s PS/2 Model 70 and claims to operate faster than either the Compaq or IBM.

A small footprint--the space occupied by the computer’s central processing unit--is a major feature of Compaq’s 386s. It is about 16 inches wide, 15 inches deep and 6 inches tall. But the real news is inside, where all the components are quickly and easily accessible.


Easy to Upgrade

Compaq’s 386s and 386/20e are especially easy for owners to upgrade. The cover can be removed with large knurled thumb screws. The floppy and tape drives are installed easily through the front of the machine and the hard drive is firmly secured with a single screw.

Four expansion slots compatible with PC XT and PC AT circuit boards are available for modems, network cards, FAX cards, scanner connectors or laser printer enhancements because the Compaqs include the video circuitry (compatible with IBM’s VGA standard), disk controllers and full memory expansion elsewhere in the computer.

Direct Comparisons


Costs vary according to the way the machines are equipped, making direct comparisons between the Compaq, IBM and ALR models difficult. However, similarly equipped 25-megahertz Compaq and ALR machines are priced at about $11,000 and $8,000, respectively. The comparably fast but less expandable IBM 25-megahertz computer with a similar 120-megabyte hard disk also lists for about $8,000.

The basic, slower Compaq 386s starts at about $5,200, with a color monitor. At the other end of the scale, you could spend nearly $52,000 to fully outfit a Deskpro 386/25 with 16 megabytes of memory, 1.2 gigabytes of data storage and a math co-processor board.

COMPAQ’S NEW COMPUTERSCompaq Computer recently added three computers using Intel’s fast 80386 microprocessors to its product line. Each includes one megabyte of random access memory, which is expandable, a 1.2-megabyte floppy drive and a choice of hard drives. In descending order of performance, they are: Compaq Deskpro 386/25. Traditional large Deskpro chassis, 20 inches wide, 16 1/2 inches deep and 6 1/2 inches tall with eight expansion slots, runs at 25 megahertz, 32-bit random access memory expandable to 16 megabytes, accommodates hard drives of 60, 110 or 300 megabytes. Use of hard drive expansion units allows up to 1.2 gigabytes of storage. Front panel works with either a second floppy drive or a tape backup drive. Choice of VGA or traditional Compaq dual-mode video displays. Price with a single 110-megabyte drive, VGA and color monitor, $11,597. Compaq Deskpro 386/20e, Compaq Deskpro 386s. Each has a small-footprint chassis at 16 inches wide, 15 inches deep and 6 inches tall. Four expansion slots, built-in VGA video capability and can accommodate two hard drives of 20, 40 or 110 megabytes. With one hard drive, the front panel works with two floppy drives plus a tape backup drive. Second hard drive eliminates one front panel device. Deskpro 386/20e runs at 20 megahertz and has 32-bit random access memory expandable to 16 megabytes. Price with a 40-megabyte hard drive and color monitor, $7,298. Deskpro 386s runs at 16 megahertz and has 16-bit random access memory expandable to 13 megabytes. Price with a 40-megabyte hard drive and color monitor, $5,898. (By comparison, IBM’s PS/2 Model 70 equipped with a 120-megabyte hard drive, VGA and color monitor is priced at $8,590 and has room for three expansion cards compatible with IBM’s Micro Channel design. Advanced Logic Research’s FlexCache 25386DT, equipped with a 120-megabyte hard disk, and VGA, but without monitor is listed at $7,989.) Manufacturer: Compaq Computer Corp., 20555 FM 149, Houston, Tex. 77269-2000, (713) 370-0670.