i currently have a gtx 660 ti 3GB. should i sell it and get a gtx 590 because the prices are around 350. or should i spent the 350 for something better?
Don't buy a 590, a 660 ti is still a fine card, if you want something new for $350 a 770 or a 280x is much much better. There won't be a huge performance gain between either of those and your 660 ti though.