Jean-Marie Descarpentries, the man credited with returning French computer maker Cie des Machines Bull to profitability, is stepping down as chairman. The 61 year-old smoothed the company’s path into the private sector and handled the unpopular task of cutting costs and selling off the personal computer business to Packard Bell Electronics Corp and NEC Corp. He is succeeded by 54-year old Guy de Panafieu, who has been poached from Lyonnaise des Eaux SA.