I'd suggest you try to install the ATI driver.
Maybe this link will help:
http://en.opensuse.org/SDB:ATI_Drive...ler_under_SUSE
First you should try to configure the built-in driver with 'sax2 -m 0=radeon'. Login as root and change the runlevel to 3 (type 'init 3'). To make sure that the chip# is correct, type 'sax2 -p', which gives a list of detected cards on your system. The ATI card should list as 0. If so, use 0=radeon, otherwise adjust accordingly.