IBM Finds Clones of Old Model Are Stiff Competition

NEW YORK — International Business Machines Corp.’s PS/2 computers have run up against an obstacle that is proving difficult to overcome: the continued popularity of clones that copy IBM’s 4-year-old PC/AT.

Since it unveiled the PS/2 in April, 1987, IBM has tried to convince users that the line’s new design is better suited than the AT’s to take advantage of the latest advances in desktop computer technology.

But industry analysts say customers are reluctant to jump on the PS/2 bandwagon and continue to buy AT clones in huge numbers.

Although the PS/2s are far from being a flop--shipments have topped 2 million units--IBM’s share of the personal computer market is eroding, in part because it no longer sells an AT-class model.

“IBM lost at least 10 market points on the decision to kill the AT while it was still a very hot product,” said Tim Bajarin, a computer industry analyst with Creative Strategies Research International.

A major reason the PS/2s have been slow to catch on is that the software that makes them easier to use and brings out the full potential of their internal architecture is still not available.

Different Data Buscq

But analysts said that even customers willing to wait for the new software are not moving to the PS/2 because they cannot retain their often large investment in add-on boards, printers and other peripherals designed for AT-class machines.

That is because most PS/2 models employ a new data bus--the circuits that connect the computer’s microprocessor with the other parts of the machine-- that cannot work with the AT’s data bus.

IBM defends its decision to switch to the new data bus, called the Micro Channel, even though it has been widely criticized for the move. It says the Micro Channel is far more powerful than the AT-bus and can take full advantage of today’s advanced microprocessors, including the Intel 80386.

But there are signs that many AT loyalists are not convinced that it is worth the trouble and expense to go with Micro Channel-based machines.

Almost half of the 2 million PS/2s shipped so far were models that do not use Micro Channel (the low-end Models 25 and 30 are based on a bus similar to that used in the first IBM PC introduced in 1981.) And Dell Computer Corp., the first company to announce PS/2 clones, said last week that it was delaying its machines because demand was weak.

Tandy Corp., however, is going ahead with plans to put PS/2 clones in its Radio Shack stores this week.

The continued success of AT clones poses a difficult problem for IBM, which stopped making its AT models in order to help establish the PS/2 as the new industry standard.

New Computer Expected

IBM would clearly like to recapture some of the AT sales now swelling the profits of clone-makers such as Tandy and Compaq Computer Corp. But it does not want to appear to be backing away from its commitment to the Micro Channel.

The solution? Analysts believe the company will unveil a computer--perhaps as soon as next month--that looks very much like an AT. It will be called a PS/2 and positioned as a big brother to the Model 30, whose Intel 8086 microprocessor is considered underpowered for most business users.

But the heart of the new computer will be all AT. It will be built around the more muscular Intel 80286 chip and will use the AT bus.

An IBM spokesman would not say whether such a computer was in the works. In February, however, company officials said the low end of the PS/2 line would eventually include 80286-based models.

Industry analysts said IBM has ordered the chip sets needed to build the AT-style PS/2 from VLSI Technology Inc. They expect it will sell for $1,800 to $2,500, the same price as most AT clones used by businesses.

But IBM’s return to the AT market does not mean it has given up on efforts to make the PS/2 the industry’s desktop computer of preference.

Could Do Both

“I would not read into this that IBM is abandoning Micro Channel,” said Stephen Cohen of Gartner Securities Corp. “It’s a very logical opportunity” to sell AT-class computers until the PS/2 takes firm hold in the industry, he said.

Richard Shaffer, editor of the Technologic Computer Letter, says there is no reason IBM cannot return to the AT-bus and still seek to establish Micro Channel as the predominant industry design.