HOUSTON (AP) _ Compaq Computer Corp. president and chief executive Michael D. Capellas was given the additional title of chairman by the company's board of directors Thursday.

Capellas, 46, succeeds Benjamin M. Rosen, 67, who is retiring after 18 years of service atop the Houston-based company's board.

The appointment is effective immediately.

Rosen said Compaq is in good hands with Capellas.

``Michael and his management team have charted the right course for the company and I believe he has clearly demonstrated the leadership Compaq needs and deserves in a chairman,'' Rosen said.

Capellas returned the compliment.

``Ben has been one of the principal architects of Compaq's success since the company was founded in 1982,'' Capellas said. ``He set the standard of excellence and visionary leadership by which all of us at Compaq measure ourselves.''

Rosen was a founding board member in 1982 and was appointed chairman the next year.

Capellas was named president and chief executive officer in July 1999, replacing ousted predecessor Eckhard Pfeiffer. Rosen temporarily took the reins that spring as the board searched for a replacement.

Rosen remains vice chairman of the board of trustees of the California Institute of Technology, and a board member of Memorial Sloan-Kettering Cancer Center, Columbia Business School and the New York Philharmonic.

He also is a director of Capstone Turbine Corp., Ask Jeeves, Inc., and idealab! Inc., which are all technology companies.

Earlier this summer, Compaq met analysts' second-quarter estimates, reporting a profit from operations of $362 million, a year after disastrous results forced layoffs and the management shake-up.

Compaq announced the change after the close of regular trading. Shares of Compaq finished up 70 cents at $29.85 at 4 p.m. on the New York Stock Exchange, but fell nearly 6 percent in the after-hours session to $28.15.