Dell, Yahoo boost techs; BlackBerry falls By: MarketWatch March 25, 2013 at 09:21 AM EDT New bidders emerged to compete with Michael Dell’s privatization deal, while BlackBerry gets downgraded by Goldman Sachs on worries about Z10 sales. Read More >> Related Stocks: AT&T Inc Apple Best Buy Blackstone Inc Macy's PHLX Semiconductor Sector Index Yahoo