The further discussion via mail was the following:
1] Update to the very latest graphics card driver.
2] Deactivate Shadows and Ambient Occlusion in the viewport settings menu since they slow down the rendering
3] The graphics card driver crashes if the viewportport takes longer than 1-2 seconds to render ( ~ 0.5 fps refresh rate ).
CE (and all other OpenGL-enabled applications at the same time) is crashed due to a timeout of the graphics card driver itself, so there's not really something we can do other than to try and prevent that the fps drops below 1fps.
Let me know if this makes sense ..