Wall Street is trying to regain its footing after a recent rebound began to lose some force. The S&P 500 and Europe's Stoxx 600 have risen in only one of the past four sessions. Investors are no longer buying everything simply because it has a ticker symbol and a pulse. But in one corner of the market, the mood remains almost aggressively enthusiastic: semiconductors. The chip sector has now posted 17 straight gains.
