display issues in opensuse 11.0

greetings all,
i have got a weird problem with my graphics. everything seems smeared, when scrolling in firefox or conqueror, the controllbar has got splotches, and so do the window bars. it looks like as if the graphics are not fast enough.
i run opensuse 11.0 kde3.5
kernel 2.6.25…
on a gateway t1616 laptop
with a wxga ultrabrighttft active matrix lcd display and ati radeon x1270 video graphics.
thanks,
theo