If you can go to around 150-190, you should get the HD 6850 or maybe the nVidia GTX 560, they both are a good bang for their buck.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814121419- HD 6850
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130660- GTX 560