[John Mulligan]

I believe that what you are looking for is an NVidia Quadro card. This is currently the high-end solution for graphics acceleration in CS4 Premiere Pro. A company called Elemental Technologies is providing a PP Plugin module that is being packaged with certain Quadro card bundles. This plugin takes advantage of the GPU capabiliities of the Quadro cards and offloads many of the rendering tasks to the GPU. Here is a link with more information:

https://www.elementaltechnologies.com/products.php?id=5