The Sensex at the Bombay Stock Exchange today rose by 80 points in early trade, extending an upward streak for the third straight session, after Reliance Industries and HCL Technologies posted encouraging fourth quarter earnings.The 30-share index, which had gained over 502 points in the previous two sessions, rose by 80 points to 18,825 in early trade.The Nifty, at the National Stock Exchange rose by 30 points to 5,719.