You probably want to get rid of the stock cooler anyway. Check these guys out - these fans don't cost hardly anything, yet they not only cool your board better, but they are also silent.
I have an x1900 XTX and I am running a cooler from these guys on it and talk about a major improvement! Not only does it run cooler, but I can't hear it anymore!!!
http://www.arctic-cooling.com/vga1.php
-S