I don't know particularly about your card,if your card is a agp4x card then it should support hardware acceleration.If you don't have hardware acceleration there is possibly two reasons ,
first that you have not configured your card properly(/etc/X11/Xfree86-4 or /etc/X11/Xfree86)
second that the driver does not support hardware acceleration that may be becoz of the manufacturer who does not release the driver or maybe because your X windows version is really old and has only primitive support for the card.(If you could have given your distribution I could have not included the previous line)
So you have two options try the website of the manufacturer(for a linux driver), or search google for your answers
http://google.com/linux
