The scene you're using is already pretty simple. I don't see how you can reduce the geomoetry complexity any further. You can of cause decrease the clipping distance to speed rendering up, but as soon as the scene gets more complex you'll get into the same trouble again. Ist this map compiled as simple or BSP map. That might also help if you own the pro edition and your map consists of lots of rooms. The scene you're showing is strange anyways. Even a low end system shouldn't be that slow for 1k triangles.