I currently have a Pci Express x16 x16 Slot. With a Geforce 8500 GT Graphics card and I want to upgrade. Can you tell me which of these are the best choice? For overal?

http://www.compusa.com/applications/SearchTools/item-details.asp?EdpNo=6076194&CatId=3669

http://www.compusa.com/applications/SearchTools/item-details.asp?EdpNo=5566458&CatId=3669

http://www.compusa.com/applications/SearchTools/item-details.asp?EdpNo=5516908&CatId=3669

http://www.compusa.com/applications/SearchTools/item-details.asp?EdpNo=4236616&CatId=3669

To help you understand - http://i41.tinypic.com/s2webd.png