* New Cirrus Chief: Cirrus Logic Inc., once a dominant maker of semiconductors for computer graphics, said Chief Executive Michael Hackworth stepped down, handing the reins to President David French. Hackworth, who remains chairman, said French needs more leeway to put a turnaround strategy in place for the struggling company. Hackworth, 58, had been CEO for 15 years.

* Baby Bell Buy: SBC Communications Inc. said it will invest $500 million in the telephone unit of gas pipeline company Williams Cos. as part of its plan to provide long-distance services. Williams expects to complete a 32,000-mile fiber-optic network, which will provide connections to 125 cities, by the end of next year.

* Put It on My EarthLink: EarthLink Network Inc., the Pasadena-based Internet service provider, introduced a Visa credit card with MBNA Corp. that gives consumers cash back for shopping on the Internet.

* Serviceable Acquisition: Computer Associates International Inc., a maker of software that runs computer networks and mainframe computers, agreed to buy consulting company Computer Management Sciences Inc. for about $435 million, or $28 a share, to expand its 10-month-old services business.