This is a XFX 6770 for $109 and $89.99 after rebate. http://www.newegg.com/Product/Product.aspx?Item=N82E16814150540
SAPPHIRE Radeon HD 6670 $64.99 and $54.99 after rebate.http://www.newegg.com/Product/Product.aspx?Item=N82E16814102988
I don't know what your using your PC for. The 6770 can run most games at 1900x1080 if you don't turn everything to max in the settings. The 6670 will be good for light gaming at 1600x900. The nvidia 670 will be out on May the 10th. But the 660(ti) isn't coming out till Q3 2012. The 6770 would be my pick if you play a lot of games and don't mind lower detail for a few months.