I have the same graphics card, and with OpenGL enabled, it really struggles with anything more than a few hundred ks worth of polygons. With nearly three million in your scene, I would guess that the problem lies in the graphics cards inability to handle that amount of data. There was a thread about this on the E-On forum before Christmas. Try turning OpenGL off and see how you get on. Alternatively, given the known problems with Vue 5 and large scenes, it could simply be a different manifestation of the memory problem - yes, even with 2 gig of physical ram ... ...