For a DirectX 11 launching point, the HD5770 from Sapphire is surprisingly a very quick and powerful videocard for little money. Right out of the box it plays with the HD4850, bullies it around the school yard then takes its lunch. Then it runs over to the HD4870, runs circles around it, and then gives it a black eye.

http://www.tweaknews.net/reviews/sap...eocard_review/