Since it doesn't appear that Carrara 8 or Carrara 8 Pro use CUDA (nvidia) or Stream (ATI) to harness the GPU in the rendering process, upgrading from one Quadro to another seems somewhat pointless (if that is the sole purpose for upgrading). Same logic would apply to the GTX 280 series (in your forum topic subject line).
Hey, COLGeek, thanks for the response, the porblem is that I aligned and learned Carrara, and I don't think there is upgrade intrest in using nvidia or ATI, so the good luck is you. I work a two year old 8400 Boxx, 8 gig, i7, 64 bit, a few terbits outside, OGNG, old guy non gammer! The cameras in Carrara are what I use to see the multiverse. Guess I got to learn Maya of something like it. Again thanks, journey well. Craig E.