I played this a lot back in 199x... On a VGA 386sx...
Kinda clunky on the 1000. The frame rate is a bit too low.
Level of detail (LOD) refers to the complexity of a 3D model representation.
LOD can be decreased as the object moves away from the camera (or some other metric, like object's importance).
Here is an example of a pretty "aggressive" LOD threshold from EA's #LHX game from 1990.
See the visual pop as the model decreases poly count!
LOD techniques increase the efficiency of rendering since they decrease the workload on the graphics pipeline stages (fewer vertex transforms).