SANTA CLARA, Calif. — Intel Corp.'s latest initiative has nothing to do with promoting a new technology. Instead, the microprocessor giant is trying to stomp out an existing one — the venerable Industry Standard Architecture bus. Intel has assembled a tiger team that aims to eliminate ISA from new PCs by the year 2000.

Intel claims the relatively slow and stodgy bus holds back the PC with its ties to register-level hardware interrupts and direct-memory access channels, creating incompatibility issues and support headaches for OEMs. Analysts said the elimination of the admittedly aging ISA bus will take longer than Intel would hope and, they noted, the effort will also aid Intel to drive more PC functions — such as audio and modem features — to its processors and chip sets.

"ISA is crippling the computer platform right now," said Jim Pappas, director for technology initiatives at Intel. "A bad-behaving ISA device can slow down other parts of a system."

Earlier this summer, Microsoft and Intel jointly released a PC '99 specification that called on PC makers to eliminate ISA completely from systems that ship after January 1, 2000.

To help drive that goal, Pappas recently set up a team under Steve Whalley, former head of USB initiative, to promote what Intel calls the legacy-free PC. The group's job for the next year is to push for the elimination of ISA cards, slots and motherboard devices. The initiative also involves a design for a streamlined audio/modem riser (AMR) card, a small AC '97 codec board that relies on chip sets and modems to handle many audio and modem features.

The push amounts to a radical rethinking of the PC, said Dean McCarron, principal of Mercury Research (Scottsdale, Ariz.), who espoused his views in a recent report, "Re-Architecting the PC." "Standalone I/O components are going to go away as all this stuff gets integrated," McCarron said. "Standalone ISA SoundBlaster audio codecs, which have been a tremendous business, will disappear, and graphics will in some cases be reduced to a RAMDAC."

But ISA will go through prolonged death throes, said Roger Kay of International Data Corp. (Framingham, Mass.). "The ISA monster is relatively big," said Kay. ISA's passing "won't happen as rapidly as Intel says it will, but it will happen eventually."

The shift away from systems that use ISA slots is already happening, Kay noted. But as many as 30 percent of the audio cards that ship worldwide in 2001 may still be relatively simple, low-cost ISA adapters, he predicted. "ISA audio cards are cheap, they do the job and Taiwan will continue to kick out these babies," Kay added.

Attacking the cost issue, Intel will remove ISA support from its standard chip sets, perhaps as early as next year, and charge extra for versions of the chips that support ISA, Pappas said. He also expects the AMR cards — expected to first appear in PCs that ship in the fall of 1999 — will become the lowest-cost means of implementing modem and audio functions.

"When there is a less-expensive way to accomplish something, the PC industry is very aggressive in adopting it," Pappas said. Audio and modem functions tend to have "pretty deep teeth" sunk into the ISA bus, he added.

The AMR cards are fundamentally just codec cards based on the AC '97 revision 2.0 standard that use a new mechanical connector to plug into an AC '97 signaling link. The cards would hand off digital processing tasks to Intel processors via upcoming Whitney and Camino chip sets from Intel. OEMs would use various versions of the cards to support different modem standards in various countries. Intel will detail the AMR spec at its developer forum in Palm Springs in September.

Analyst Kay said that while all PC audio lived on ISA back in 1995, as little as 20 percent of audio cards that ship in the United States in 1999 will use ISA. While PCI audio is on the rise, so is Intel's host-based audio push. "Host-based digital audio will be about half of the market in the United States by 2001," said Kay.

Creative Labs (Milpitas, Calif.), which developed the broadly used, ISA-based SoundBlaster technology, has struggled through the shift to PCI, fielding its first PCI audio cards this year. Micah Stroud, audio marketing manager, said that while many companies are offering SoundBlaster support over PCI in hardware or software, the pull to ISA is still strong.

Compatibility with existing software far outweighs cost savings that might be achieved by moving to PCI, Stroud said. For instance, a large installed base of children's games runs on ISA-based audio, and moving to PCI renders many of them unusable because they cannot tap into the interrupts and DMA channels SoundBlaster titles seek, he added.

Stroud said the shift from ISA won't kick into gear until the first half of next year, when Intel rolls out motherboards without the ISA bus. For its part, Microsoft has promised it will offer software support for SoundBlaster audio through a future version of its DirectX API.

Another part of the ISA attack aims at motherboard devices, typically Super I/O controllers. Intel has been working with a handful of companies to develop a so-called Low Pin Count connection that weans these chips off ISA. LPC uses four to seven pins instead of 50.

The LPC interface is expected to appear on Intel's chip sets next year. Standard Microsystems Corp. (Hauppauge, N.Y.) is sampling Super I/O chips for LPC now.

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