ok - good thing i used the word 'sometimes
amd/ati no longer support your card, and hence don't make drivers for it any more. this page
suggests you try with a vista driver instead, but i really don't know if it will be newer than the one you have.
don't bother with the full software suite download, just the wdm driver. if it won't install, try it in vista compatibility mode (right-click on driver >> properties >> compatibility >> tick the first box and choose one of the vista options).
i'm not an expert on these old cards, so as i've said i don't know if it will be any newer than the driver you currently have.
please also fill out your system specs
which may help others offer better advice.