I just research your card in amd.com
11.10 is update driver.
but once you install it then there are no success boot into windows.
May be reformat your system is option.
AGP card driver once it start having a trouble you... this is only way to fix is reformat.
i have ati 5770 but there no problem update every driver they give me.
Unless if you don't have problems with 11.5 please you don't have to update every time new driver come out~ ^^