You can choose to display the model or one of several simplified geometric entities in the Preview dialog box. If your SolidWorks model is complex, it is helpful to use simplified geometry to improve the performance of the preview display.
To change the model in the Preview dialog box:
From the Preview dialog box, click Geometry and select or clear one of the five simplified geometric entities:
Selected Reference
Cube
Plane
Cylinder
Sphere
Torus
Click Geometry, Model to return to a preview of your model.