Zotac Geforce GT 430
http://www.amazon.com/gp/product/B00471D1OK/ref=oh_details_o00_s00_i00
or
ATI Radeon 4670 AGP
http://www.newegg.com/Product/Product.aspx?Item=N82E16814161284
http://www.amazon.com/gp/product/B00471D1OK/ref=oh_details_o00_s00_i00
or
ATI Radeon 4670 AGP
http://www.newegg.com/Product/Product.aspx?Item=N82E16814161284