OK, I've had a Dell M4400 for almost 2yrs, so it's time. . . . I got an Asus i7 Q720 with win7 64bit and 8gb ram, 17in Screen and a monster graphics card (Radeon 5870), the thing is a beast. I did some speed testing and was surprised at the result. It seems that with most single thread stuff the speed is about the same, but . . .... . check it!
The testing we have done shows that there is not much speed difference with different video cards. We have found the most change in speed from faster processors and more memory.
Eventhough PTC suggests the Quadro or FireGL cards I don't think it matters if you use a game card or not (they are much less expensive). Having the openGL drivers is absolutely required though.
We have assemblies that take 4 to 6GB of memory to open, but they run the same on a system with all the video cards we have tried on it. I can't wait for Pro/E to make use of the GPU capabilities. In theory that could speed up the system substantially.
I had a hard time following your video, so not sure I understood it.