The Sensex closed with a gain of 40 points at 13,131.Reliance Energy advanced 7% (Rs 33) to Rs 511. ONGC gained nearly 5% (Rs 39) to Rs 878.Gujarat Ambuja moved up over 3% to Rs 123. Dr. Reddy's and HDFC added over 2% each to Rs 781 and Rs 1,480, respectively.While Reliance was up Rs 3 at Rs 1,287, SBI was up Rs 2 at Rs 1,126.Tata Motors slipped nearly 2% (Rs 14) to Rs 815. TCS was down over 1% to Rs 1,067. Infosys dropped Rs 10 to Rs 2,075. Satyam, Wipro and Bharti also declined today.Declines were ahead of advances - out of 2,602 scrips traded, 1,408 declined and 1,116 moved up today.Reliance was the most active counter with a turnover of Rs 152 crore followed by Kalyani Steel (Rs 91 crore), McDowell (Rs 80 crore), Reliance Capital (Rs 74 crore) and Hindustan Zinc (Rs 71 crore).