vtk problem

I have installed CAELinux on a Dell GX520 ( Intel integrated graphic chip i950) , and I have a problem with the vtk viewer of Salome. When I change something in the view ( rotation, translation, zoom ...), the view is not refreshed. When doing the same thing on my home computer ( Ati Radeon 7200 ) , I do not have any problem. I do not only have this problem with the vtk viewer, some widgets are sometimes not refreshed.
Any idea of where the problem comes from ?
Marc

I found a solution.
I use now Xorg without hardware 3D acceleration, and now it is fine.
Marc