to add to above:.. oops, 
**
quote:** "Try zooming in to a scene and pan around, then from a distance. If the slowdown occurs at a distance alot more then up close, then a video upgrade would help more...",

... that can work backwards with textures and OpenGL views sometimes and is more in line with geometry at a distance slowdowns etc. 

So basically where there is more to be seen(lighting, textures, number of objects etc), sometimes up close, sometimes at a distance, the more your video card will have to work(I always run out of edit time, lol). A faster video card will help a great deal. Sorry for the confusion.