Yeah I would look into a new card. As good as the 48xx cards were they are way passed their prime. I retired my 4850 CF setup last year since it was was really struggling with even games at 1680x1050. 6xxx series card are closing out.

http://www.newegg.com/Product/Produc...82E16814102987

If you have a CF board adding another 4890 would be an option but I wouldn't pay much for one.