Best Laptop for Computer Science Student ( College )?

1.) i3 Or i5 2.) Atleast 4gb Ram 4.) Good battery life (not less than 6hours) 5.) EXTENSIVE internet usage 6.) Budget : Maximum $940 or (Rs 50000) 8.) Will be watching video lectures and movies(not blu ray or hd in particular)(not that big a priority) PS: Dont reccomend Sony(i know it doesnt stand up to the rest) or Apple(highly overpriced) If possible i'd like reccomendations from ASUS , Dell, Thinkpads, Lenovo, HP