OpenGL* 3-D screen savers run slowly.
Hardware acceleration for OpenGL screen savers isn't enabled in the graphics drivers because of potential compatibility issues with a number of third-party OpenGL screen savers.
Running the screen savers in software mode should reduce the possibility of system lockups or crashes while these screen savers are enabled. This shouldn't prevent these screen savers from running, but slow rendering speed may be seen. This doesn't affect OpenGL-based games or general applications.
This is expected behavior.