LORD OF CHAOS MANOR : Hoping for a message from a long-lost friend.

Eight years ago, when his friend, retired civil servant Dan MacLean, told him he should buy a computer, science fiction writer Jerry Pournelle was skeptical.

After all, Marilyn Niven, the wife of Pournelle’s writing partner, Larry Niven, with whom Pournelle had just written the best-selling “Lucifer’s Hammer,” had one. And all Larry Niven did with it was play games.

And MacLean called his Imsai home computer Alice. Pournelle thought that Alice was just another phase MacLean was enjoying. MacLean’s earlier obsessions included conjuring, rock hounding, ham radio and printing.

When a publisher offered to reprint a pair of his older novels, and he contemplated retyping them on his IBM Selectric to make minor changes throughout, Pournelle followed a course he would later codify as Pournelle’s Law: “If you don’t know what you’re doing, deal with those who do.”

He let MacLean introduce him to consultant Tony Pietsch, who, for $12,000 of borrowed money, built from a kit a computer that Pournelle named Ezekiel, Zeke for short. The name came from Zeke’s central processing unit, a Zilog Z-80 microchip.

Soon, at first using Electric Pencil word-processing software now considered primitive, Pournelle and Niven wrote another science fiction adventure, “Oath of Fealty.” Marilyn and Larry Niven bought duplicates of Zeke.

MacLean, whose every attempt to write was wooden and unproductive, learned computer programming, explored technical aspects of the microcomputer revolution and took Pournelle along.

“What this world needs is computer reviews by users ,” Pournelle wrote, quoting “my mad friend Mac- Lean,” five years ago in Pournelle’s first regular column in Byte, the respected computer monthly. Zeke, MacLean, the entire Pournelle family and their house in the foothills near Hollywood, which he renamed Chaos Manor, became continuing characters as Pournelle wrote his way into the front rank of computer journalists.

Irreverent, cantankerous, partisan, he created a backlash against software firms that installed copy-protection devices that limited legitimate use. And he ridiculed naively premature announcements of new computer products with his ironic prediction that they would be available “real soon now.”

As MacLean had predicted, an avalanche of free computer software, followed by a steady stream of review hardware, descended upon Chaos Manor, but Pournelle was left to examine it alone. He reported in the User’s Column:

“I often start these columns with a quote from my mad friend. Alas, I’ll never be able to do that again. Dan MacLean died of cancer in December.”

Two months later, Pournelle reported the death of “poor old Ezekiel, who happens to be a Cromenco Z-2 computer. I suppose I shouldn’t be surprised. Several million words went through Zeke. He was running constantly 18 hours a day for nearly five years, and in all that time he wasn’t out of service for more than a week.”

His CPU was salvaged and combined with that of Alice, MacLean’s old Imsai, within a computer used by the Los Angeles Science Fantasy Club.

So Zeke II, with a faster six-MHz CPU and much greater memory on his twin disks, came to live at Chaos Manor. Pournelle and Niven used him to write their latest novel, “Footfall.” Although Pournelle called Zeke II his “ideal writing system,” he could find no replacement for his first computer friend.

“My wife keeps telling me that one night I’ll go to sleep at the keyboard and wake to find a long message from MacLean. I hope she’s right. I could use a dose of his clear vision, and he was about the best phrasemaker I’ve ever known.”