It sounds like you are looking for a way to display dense polygon meshes in near real-time?
You might want to look at dual SLI, as I believe that would go far to help you with the geometry handling in the viewport.
....I could be wrong tho...
My hardware guy has been building my rigs for me for more than 10 yrs, but here is my current NewEgg wish list for the rig I am getting in the 14th:
(note, the video card is cheap, but it's the same production-proven card in use by my friends at Rainmaker Visual Effects
Israel "Izzy" Long
Motion and Title Design for Broadcast-Film-DS