Video card makers are going in the direction now of using the GPU as well, for floating point calculations to aid the CPU(confirming that CPUs are hitting a virtual wall). There are lots of things a video card can help with, especialy rendering certain scenes. i.e...just look at how game graphics are compared to a Bryce rendering of the same settings, and how fast the video card renders scenes. Then you could add a nice video card to your Quad setups.