just found these little links they could be useful
as the title says How To: Identify a "Build By ATI" vs "Powered by ATI"
If you know your ATI # use this link
http://apps.ati.com/102lookup/index.asp
If you don't know your ATI # and want to know how to find it use this link
http://www.ati.com/support/identify/cardver.html
hope it helps