Control Data Corp. said earnings rose 7%...

Control Data Corp. said earnings rose 7% for the first quarter to $7.7 million, compared to $7.2 million for the year-ago quarter. The Minneapolis computer company, which last year recovered from two years of huge losses, was aided by a tax credit of $3.1 million. The company said first-quarter results reflect the strength of its Data Storage Products Group--a major part of Control Data that has run into trouble in the past due to increasing competition for sales of disk drives--but the company would not provide details about the performance of the group. The company said its other major unit, its computer systems group, showed “a small profit before interest and taxes” despite lower revenue due to lower sales of some of its mainframe computers.