Best for $300
http://www.newegg.com/Product/Product.aspx?Item=N82E16814202061
If you want an Nvidia card
http://www.newegg.com/Product/Product.aspx?Item=N82E16814121637&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-na-_-na-_-na&cm_sp=&AID=10446076&PID=3938566&SID=
If you can't live without a 700 series card
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130932&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-na-_-na-_-na&cm_sp=&AID=10446076&PID=3938566&SID=